Fix isort issues

[Eric-Arellano]

#6166 correctly upgraded isort, but resulted in some files having issues that don't throw issues in CI until a related file is changed, e.g. the backend/jvm port complaining about init code.

How changes generated

• ./pants fmt src/python/pants/::
• ./pants fmt tests/python/pants_test/::
• Running similar command on every contrib/src and contrib/tests folder

Let me know if there's a better way to do this! I'm not sure I caught every problem.

[jsirois]

The best way is just ./pants fmt ::, but you probably tried that and found bad targets under testprojects/. So then ./pants --exclude-target-regexp=testprojects/ fmt :: gets around that but is slow and skips testprojects/**. A faster method for full coverage - though much less obvious is ./pants filter --type=python_library,python_tests,python_binary :: | xargs ./pants fmt. Using that I find these extra files need formatting:

testprojects/src/python/coordinated_runs/creator.py
testprojects/src/python/coordinated_runs/waiter.py
testprojects/src/python/interpreter_selection/resolver_blacklist_testing/import_futures.py
testprojects/src/python/interpreter_selection/resolver_blacklist_testing/main.py

Those are not of great concern though so - since this is green and CI is quiet I'm going to merge.