Improve pre-commit workflow (#2602)

* feat: add `isort` to `pre-commit`

* ci: skip `__init__.py` file for `isort`

* ci: make `isort` mandatory in lint pipeline

* docs: add a section on Git hooks

* ci: check isort diff

* fix: isort from master branch

* docs: add pre-commit badge

* ci: update black + bandit versions

* feat: add PR template

* refactor: PR template

* ci: remove bandit

* docs: add Black badge

* ci: try to remove all `|| true` statements

* ci: remove lint_python job

- Remove `lint_python` CI job
- Move `pyupgrade` job to `pre-commit` workflow

* fix: avoid messing with typing

* docs: add a note on running `pre-cpmmit` manually

* ci: apply `pre-commit` to the whole codebase

tests/vector/test_numpy_utils.py

@@ -1,14 +1,13 @@
-import pytest
-import numpy as np
-
 from collections import OrderedDict
 
-from gym.spaces import Tuple, Dict
+import numpy as np
+import pytest
+
+from gym.spaces import Dict, Tuple
+from gym.vector.utils.numpy_utils import concatenate, create_empty_array
 from gym.vector.utils.spaces import _BaseGymSpaces
 from tests.vector.utils import spaces
 
-from gym.vector.utils.numpy_utils import concatenate, create_empty_array
-
 
 @pytest.mark.parametrize(
     "space", spaces, ids=[space.__class__.__name__ for space in spaces]