ref(shared-views): Remove starred view logic from get /groupsearchviews/ endpoint

[MichaelSun48]

depends on #89235 being deployed

This PR refactors the GET /group-search-views/ endpoint. Previously, it used to return a user's starred views if no query params were provided. That logic has now been removed in this PR, and it has been relocated to GET /group-search-views/starred to reduce overloading of this endpoint.

[MichaelSun48]

Previously, if no query params were passed into this endpoint, it would return the user's starred views.

That default behavior has now been removed, and it defaults the query params to createdBy = "me" and sort = "-visited" if none are passed in.

[MichaelSun48]

Besides removing tests that accounted for the old logic, the other changes in this file are mostly reducing boilerplate code.

For example, the BaseGSVTestCase (which creates a fixed set of test data) has been removed in favor of GroupSearchViewAPITestCase, which instead provides handy functions like create_view and star_view. This helps reduce all of those GroupSearchView.objects.create(...) calls that took up too much space.

[MichaelSun48]

This test class depended on the BaseGSVTestCase, and refactoring it out of this file in favor of GroupSearchViewAPITestCase turned out to be a bit more work than I expected. I will do this in a separate PR.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

✅ All tests successful. No failed tests found.

Additional details and impacted files

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