CompatHelper: bump compat for OrdinaryDiffEqSSPRK to 2 for package test, (keep existing compat)

[github-actions]

This pull request changes the compat entry for the OrdinaryDiffEqSSPRK package from 1.2 to 1.2, 2 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.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 0.00%. Comparing base (b728f76) to head (f873398).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #143       +/-   ##
==========================================
- Coverage   99.28%   0.00%   -99.28%     
==========================================
  Files          96      95        -1     
  Lines        5147    4925      -222     
==========================================
- Hits         5110       0     -5110     
- Misses         37    4925     +4888     

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