[flake8-bandit] Make example error out-of-the-box (S412)

[MeGaGiGaGon]

Summary

Part of #18972

This PR makes suspicious-httpoxy-import (S412)'s example error out-of-the-box. Since the checked imports are classes instead of modules, the example isn't valid. See #19009 for more details

PS ~>py -c "import wsgiref.handlers.CGIHandler"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
    import wsgiref.handlers.CGIHandler
ModuleNotFoundError: No module named 'wsgiref.handlers.CGIHandler'; 'wsgiref.handlers' is not a package
PS ~>py -c "from wsgiref.handlers import CGIHandler"
PS ~>

Old example

import wsgiref.handlers.CGIHandler

New example

from wsgiref.handlers import CGIHandler

Test Plan

N/A, no functionality/tests affected

[github-actions]

ruff-ecosystem results

Linter (stable)

✅ ecosystem check detected no linter changes.

Linter (preview)

✅ ecosystem check detected no linter changes.

[ntBre]

Thanks!

How'd you install wsgiref? I was trying with uv while writing up #19242, but it was complaining about print statements without parentheses 😆