CompatHelper: bump compat for VLBILikelihoods to 0.3, (keep existing compat)

[github-actions]

This pull request changes the compat entry for the VLBILikelihoods package from ^0.2.6 to ^0.2.6, 0.3.
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 89.83%. Comparing base (15dec4a) to head (5634a02).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #456   +/-   ##
=======================================
  Coverage   89.83%   89.83%           
=======================================
  Files          44       44           
  Lines        2941     2941           
=======================================
  Hits         2642     2642           
  Misses        299      299           

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