CompatHelper: add new compat entry for SparseMatrixColorings at version 0.4 for package test, (keep existing compat)

[github-actions]

This pull request sets the compat entry for the SparseMatrixColorings package to 0.4 for package test.
This keeps the compat entries for earlier versions.

Note: I have not tested your package with this new compat entry.
It is your responsibility to make sure that your package tests pass before you merge this pull request.
Note: Consider registering a new release of your package immediately after merging this PR, as downstream packages may depend on this for tests to pass.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 37.40%. Comparing base (9f50690) to head (6486df6).
⚠️ Report is 3 commits behind head on main.

❗ There is a different number of reports uploaded between BASE (9f50690) and HEAD (6486df6). Click for more details.

HEAD has 116 uploads less than BASE

Flag	BASE (9f50690)	HEAD (6486df6)
DI	106	2
DIT	24	12

Additional details and impacted files

@@             Coverage Diff             @@
##             main     #879       +/-   ##
===========================================
- Coverage   98.15%   37.40%   -60.75%     
===========================================
  Files         134      126        -8     
  Lines        8018     7835      -183     
===========================================
- Hits         7870     2931     -4939     
- Misses        148     4904     +4756     

Flag	Coverage Δ
DI	13.32% <ø> (-85.54%)	⬇️
DIT	96.39% <ø> (ø)

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