CompatHelper: bump compat for DifferentiationInterface to 0.7 for package DifferentiationInterfaceTest, (keep existing compat)

[github-actions]

This pull request changes the compat entry for the DifferentiationInterface package from 0.7.7 to 0.7.7, 0.7 for package DifferentiationInterfaceTest.
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 91.36%. Comparing base (ed5655a) to head (b1750b2).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #845   +/-   ##
=======================================
  Coverage   91.36%   91.36%           
=======================================
  Files         133      133           
  Lines        7887     7887           
=======================================
  Hits         7206     7206           
  Misses        681      681           

Flag	Coverage Δ
DI	89.70% <ø> (ø)
DIT	95.69% <ø> (ø)

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