Avoid module lookup for known classes when possible

[MichaReiser]

Summary

Avoid calling file_to_module when resolving known classes unless
the class name matches the name of a known class.

I don't expect this to change performance in a significant way (there aren't enough classes)

Test Plan

cargo test

[github-actions]

ruff-ecosystem results

Linter (stable)

✅ ecosystem check detected no linter changes.

Linter (preview)

✅ ecosystem check detected no linter changes.