Deprecate logging.getLevelName(str)

[srittau]

See https://docs.python.org/3/library/logging.html#logging.getLevelName

[srittau]

See also #12088 and #12092 for prior discussion.

[github-actions]

Diff from mypy_primer, showing the effect of this PR on open source code:

mitmproxy (https://github.com/mitmproxy/mitmproxy)
+ mitmproxy/log.py:193: error: Argument "level" to "log" of "Logger" has incompatible type "str"; expected "int"  [arg-type]

pytest (https://github.com/pytest-dev/pytest)
+ src/_pytest/logging.py:520: error: Argument 1 to "getLevelName" has incompatible type "str"; expected "int"  [arg-type]

mkosi (https://github.com/systemd/mkosi)
+ mkosi/log.py:92:55: error: Argument 1 to "getLevelName" has incompatible type "str"; expected "int"  [arg-type]

[srittau]

Looking at the primer output: mitmproxy uses it in a method that's deprecated itself, pytest's use looks valid, although it could use more explicit code instead, and mkosi's use is unnecessary, as setLevel accepts str levels.

[github-actions]

According to mypy_primer, this change has no effect on the checked open source code. 🤖🎉