Fix collection homepage assigining

[dominik-zeglen]

I want to merge this change because it changes how 'Feature on Homepage' switch behaves - from in-place mutation to waiting for confirmation by 'Save' button.
Build on top of #3474

Pull Request Checklist

1. Privileged views and APIs are guarded by proper permission checks.
2. All visible strings are translated with proper context.
3. All data-formatting is locale-aware (dates, numbers, and so on).
4. Database queries are optimized and the number of queries is constant.
5. Database migration files are up to date.
6. The changes are tested.
7. The code is documented (docstrings, project documentation).
8. GraphQL schema and type definitions are up to date.
9. Changes are mentioned in the changelog.

[codecov]

Codecov Report

Merging #3481 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #3481   +/-   ##
=======================================
  Coverage   89.89%   89.89%           
=======================================
  Files         241      241           
  Lines       13109    13109           
  Branches     1323     1323           
=======================================
  Hits        11784    11784           
  Misses        921      921           
  Partials      404      404

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