Cleanup ng test

[Xiphoseer]

Angular generates test cases with every component template, but we haven't actually run those up until now. This branch adds the common modules to the test fixtures in the majority of places. The idea is to gate on ng test running in the future using GH actions.

// cc: @lcdr

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[lcdr]

Getting tests working and integrated with CI is definitely a good idea. I have no experience with Angular testing, so I'll trust you that the changes are reasonable, feel free to merge.

[Xiphoseer]

I guess the main question is whether it makes sense to need to specify the "global" service modules and pipes that are loaded by app.module.ts in production for every component that uses them individually, which is what this PR is doing.

I think there'd be a way to register e.g. LuJsonService for all components by default and override it for mocks, but it may also catch more bugs to do it case by case.