Fix pylint 2.11 consider-using-f-string checker errors

[weiji14]

Description of proposed changes

Pylint v2.11.1 released on 17 Sep 2021 added a few more checks, most notably, a recommendation to use f-strings (C0209), and a couple of other ones.

pylint pygmt setup.py doc/conf.py
************* Module pygmt.figure
pygmt/figure.py:106:38: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/figure.py:361:24: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/figure.py:363:24: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
************* Module pygmt.src.grd2cpt
pygmt/src/grd2cpt.py:170:24: C0201: Consider iterating the dictionary directly instead of calling .keys() (consider-iterating-dictionary)
************* Module pygmt.src.legend
pygmt/src/legend.py:89:34: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
************* Module pygmt.src.makecpt
pygmt/src/makecpt.py:154:20: C0201: Consider iterating the dictionary directly instead of calling .keys() (consider-iterating-dictionary)
************* Module pygmt.src.surface
pygmt/src/surface.py:108:38: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
************* Module pygmt.src.x2sys_cross
pygmt/src/x2sys_cross.py:204:20: W1514: Using open without explicitly specifying an encoding (unspecified-encoding)
************* Module pygmt.src.config
pygmt/src/config.py:59:13: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/src/config.py:70:13: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
************* Module pygmt
pygmt/__init__.py:80:25: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/__init__.py:215:20: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
************* Module pygmt.src.meca
pygmt/src/meca.py:458:34: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
************* Module pygmt.clib.session
pygmt/clib/session.py:192:16: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/clib/session.py:369:16: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/clib/session.py:415:16: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/clib/session.py:465:16: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/clib/session.py:506:16: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/clib/session.py:653:16: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/clib/session.py:660:18: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/clib/session.py:664:16: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/clib/session.py:674:16: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/clib/session.py:908:31: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/clib/session.py:977:31: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/clib/session.py:1086:35: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
************* Module pygmt.tests.test_clib
pygmt/tests/test_clib.py:156:36: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:367:44: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:370:17: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:372:23: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:489:44: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:492:17: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:494:23: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:550:44: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:553:17: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:555:23: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:582:44: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:585:17: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:587:23: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:605:44: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:608:17: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:610:23: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:631:44: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:635:20: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:639:23: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:654:40: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:657:13: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:659:19: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:689:34: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/tests/test_clib.py:696:34: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
************* Module conf
doc/conf.py:130:13: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
************* Module pygmt.helpers.testing
pygmt/helpers/testing.py:116:24: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
************* Module pygmt.helpers.decorators
pygmt/helpers/decorators.py:471:27: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pygmt/helpers/decorators.py:693:16: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)

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Your code has been rated at 9.90/10

Luckily there was a tool called flynt that semi-automatically did the f-string conversion, so I only had to manually change some that weren't caught. Let me know if you find any more!

Also made some edits where dict.keys() was not required anymore, and a missing encoding from pathlib.Path.read_text()

Fixes #

Reminders

• Run make format and make check to make sure the code follows the style guide.
• Add tests for new features or tests that would have caught the bug that you're fixing.
• Add new public functions/methods/classes to doc/api/index.rst.
• Write detailed docstrings for all functions/methods.
• If adding new functionality, add an example to docstrings or tutorials.

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