Stop at the first resolved parent configuration

[MichaReiser]

Summary

This is a potential fix for #8858 but requires some more testing.
I'm throwing this out here to get some feedback on whether this seems correct. The following is my reasoning, although I'm not very familiar with the code.

The idea of visiting all ancestor paths is to find a configuration for the current directory (or given path).
Visiting the ancestors is necessary if the configuration happens to be in a parent directory. For example when running ruff in a sub-directory of the project.

This PR changes the implementation to stop at the first found configuration instead of visiting the entire project chain.
One potential issue this could introduce is:

root:
  - pyproject.toml (excludes subdir)
  - subdir
    - pyproject.toml
      - sub-sub-dir
        - some-python files 

Running ruff in sub-sub-dir would lint no files in the old version because the files are excluded by the root pyproject.toml.
The new version lints the files in the sub-sub-dir because it finds the subdir/pyproject.toml as the closest pyproject.toml and it
does not exclude the directoy.

The new behavior seems more correct to me, but I might be overlooking something.

Fixes #8858

Test Plan

Added regression test.

[MichaReiser]

Current dependencies on/for this PR:

• main
  • PR Stop at the first resolved parent configuration #8864 👈

This stack of pull requests is managed by Graphite.

[MichaReiser]

This is a potential breaking change

[github-actions]

ruff-ecosystem results

Linter (stable)

✅ ecosystem check detected no linter changes.

Linter (preview)

✅ ecosystem check detected no linter changes.

[charliermarsh]

This looks correct to me.