Alter fallback for source-roots

[akamat10]

Type of Changes

	Type
✓	✨ New feature
✓	📜 Docs

Description

Alter fallback for source-roots as discussed in #9955. This simplifies the import discovery logic, makes it easier to understand and supports the discovery process for more usecases (for example, src-layout or in cases where imported modules may be in a different directory from the files to be linted)

TODO:

• Changelog
• Documentation

Update changelog and documentation

Closes #9955

[codecov]

Codecov Report

Attention: Patch coverage is 83.33333% with 2 lines in your changes missing coverage. Please review.

Project coverage is 95.80%. Comparing base (c0ecd70) to head (fed3e42).
Report is 27 commits behind head on main.

Files with missing lines	Patch %	Lines
pylint/lint/expand_modules.py	83.33%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9967      +/-   ##
==========================================
- Coverage   95.80%   95.80%   -0.01%     
==========================================
  Files         174      174              
  Lines       18934    18939       +5     
==========================================
+ Hits        18140    18144       +4     
- Misses        794      795       +1     

Files with missing lines	Coverage Δ
pylint/lint/pylinter.py	96.65% <ø> (ø)
pylint/pyreverse/main.py	93.75% <ø> (ø)
pylint/lint/expand_modules.py	94.44% <83.33%> (-0.85%)	⬇️

[DudeNr33]

As this is not primarily about pyreverse, I have unassigned me from the review.

[github-actions]

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

This comment was generated for commit fed3e42

[DanielNoord]

@akamat10 Can you tag me when this is ready for review?

[akamat10]

Will do!