Changed python req to >= 3.8

Changed the requirement to 3.8 to avoid the pickle 5 protocol impatibility bug since it only supports from python3.8

Author: ForFoxSakes

recipe/meta.yaml

@@ -23,7 +23,7 @@ requirements:
     - python
     - setuptools
   run:
-    - python <3.9  # https://github.com/conda-forge/pyside2-feedstock/issues/56
+    - python>=3.8, <=3.9   # https://github.com/conda-forge/pyside2-feedstock/issues/56
     - numpy >=1.20.2
     - arrow
     - brightway2 >=2.1.2