Replace deprecated `pkg_resources` with `importlib.metadata`

[enoch85]

The pkg_resources module is deprecated and scheduled for removal in late 2025. This causes a warning in applications using pybotvac:

/usr/local/lib/python3.13/site-packages/pybotvac/version.py:1: UserWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html. The pkg_resources package is slated for removal as early as 2025-11-30.

Suggested fix

Replace in version.py:

import pkg_resources
__version__ = pkg_resources.get_distribution("pybotvac").version

With:

from importlib.metadata import version
__version__ = version("pybotvac")

importlib.metadata is available in Python 3.8+ and is the recommended replacement.