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

setup.py

@@ -1,6 +1,6 @@
+import itertools
 import os.path
 import sys
-import itertools
 
 from setuptools import find_packages, setup
 
@@ -20,7 +20,7 @@ extras = {
 }
 
 # Meta dependency groups.
-nomujoco_blacklist = set(["mujoco", "accept-rom-license", "atari"])
+nomujoco_blacklist = {"mujoco", "accept-rom-license", "atari"}
 nomujoco_groups = set(extras.keys()) - nomujoco_blacklist
 
 extras["nomujoco"] = list(
@@ -28,7 +28,7 @@ extras["nomujoco"] = list(
 )
 
 
-all_blacklist = set(["accept-rom-license"])
+all_blacklist = {"accept-rom-license"}
 all_groups = set(extras.keys()) - all_blacklist
 
 extras["all"] = list(