Expand the phpunit test coverage for module_filter

Updated issue summary, with what you added in #2 and added a bit more detail. This is not a definitive list, necessarily.

I'm going to work on a javascript test for the permissions filter, as that is needed before any more work on ✨ Filter permissions on description not just module name Fixed

Permissions filter test added, ready for review.

Thanks for merging.
Putting this issue back to Active.

Updated IS for tests added in 🐛 Radio buttons on Available updates report do nothing Active

So is the tests for the extend page all that is missing you would say?

Believe we are good with coverage!