CompatHelper: bump compat for TrixiTest to 0.2 for package test, (keep existing compat)

This pull request changes the compat entry for the `TrixiTest` package from `0.1` to `0.1, 0.2` 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.