STYLE: upgrade flake8

[MarcoGorelli]

Issue here is:

1. checkout the create-pr-action/pre-commit-config-update-0 branch
2. run pre-commit run flake8 --all-files. You should see some errors like:

pandas/tests/indexes/categorical/test_formats.py:24:89: E501 line too long (98 > 88 characters)
pandas/tests/indexes/categorical/test_formats.py:55:89: E501 line too long (98 > 88 characters)
pandas/tests/indexes/categorical/test_formats.py:89:89: E501 line too long (90 > 88 characters)
pandas/tests/frame/test_query_eval.py:917:17: B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
pandas/tests/frame/test_query_eval.py:917:26: B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
pandas/tests/frame/test_query_eval.py:958:17: B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
pandas/tests/frame/test_query_eval.py:958:26: B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
pandas/core/strings/object_array.py:375:69: B023 Function definition does not bind loop variable 'pat'.
pandas/tests/window/test_rolling.py:819:10: B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
pandas/tests/window/test_rolling.py:867:10: B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
pandas/tests/window/test_rolling.py:917:10: B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
pandas/tests/window/test_rolling.py:969:10: B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
pandas/tests/io/parser/test_c_parser_only.py:194:49: B023 Function definition does not bind loop variable 'actual_val'.
pandas/tests/window/test_expanding.py:221:10: B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
pandas/tests/window/test_expanding.py:240:10: B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
pandas/tests/arrays/categorical/test_repr.py:321:89: E501 line too long (97 > 88 characters)
pandas/tests/arrays/categorical/test_repr.py:354:89: E501 line too long (97 > 88 characters)
pandas/io/formats/excel.py:175:6: B019 Use of `functools.lru_cache` or `functools.cache` on methods can lead to memory leaks. The cache may retain instance references, preventing garbage collection.
pandas/tests/arrays/masked/test_arithmetic.py:58:9: B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
pandas/tests/arrays/masked/test_arithmetic.py:217:9: B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
pandas/tests/groupby/transform/test_transform.py:760:9: B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
pandas/tests/indexes/multi/test_formats.py:186:89: E501 line too long (95 > 88 characters)
scripts/no_bool_in_generic.py:42:21: B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
pandas/tests/io/sas/test_sas7bdat.py:323:17: B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
pandas/io/pytables.py:4131:38: B023 Function definition does not bind loop variable 'obj'.
pandas/io/pytables.py:4[132](https://github.com/pandas-dev/pandas/runs/7809209712?check_suite_focus=true#step:4:134):39: B023 Function definition does not bind loop variable 'obj'.
pandas/io/pytables.py:4133:39: B023 Function definition does not bind loop variable 'obj'.
pandas/io/pytables.py:4144:38: B023 Function definition does not bind loop variable 'op'.
pandas/io/pytables.py:4145:36: B023 Function definition does not bind loop variable 'obj'.
pandas/io/pytables.py:4151:59: B023 Function definition does not bind loop variable 'obj'.
pandas/io/pytables.py:4155:43: B023 Function definition does not bind loop variable 'obj'.
pandas/io/pytables.py:4157:38: B023 Function definition does not bind loop variable 'op'.
pandas/io/pytables.py:4158:36: B023 Function definition does not bind loop variable 'obj'.

3. Fixup these errors, and when pre-commit run flake8 --all-files passes, stage, commit, and push!

[jmoro0408]

take

[jmoro0408]

Hello, I'll try taking this on as my first contribution.

[twoertwein]

A few of them are new checks from flake8-bugbear. Might need some discussion on whether some of the should purposefully be disabled (generally/line-by-line):

B019 Use of functools.lru_cache or functools.cache on methods can lead to memory leaks. The cache may retain instance references, preventing garbage collection.
B020 Found for loop that reassigns the iterable it is iterating with each iterable value.
B023 Function definition does not bind loop variable '...'.

[MarcoGorelli]

Could we just ignore them for now, so we can get the upgraded versions, and have a todo or an issue about enabling them?

[jmoro0408]

Sounds good to me. I'll just add some "# noqa" comments to the bugbear issues for now, and can discuss enabling them in a later issue.

[MarcoGorelli]

Might be easier to ignore them in the setup. Cfg file if they're codes that need discussion or that we might want to enable later

[jmoro0408]

Yep that definitely makes more sense, thanks! I'll try to get to this today.