[Testathon] Community/Collection item counts and author facets not updated after deletion

[Kasinhou]

Describe the bug

During testing T081, this bug was discovered.
Counts in Community List are not updated after deleting an item or a collection (including all its items).

Similarly, the Author facet in browse/search retains entries from deleted items even though clicking them returns no results.

To Reproduce

Steps to reproduce the behavior:

1. Navigate to an existing sub-community (or create one).
2. Create a new collection inside it.
3. Create at least one item in that collection with an author.

5. Delete the collection (which also removes its items).
6. Navigate to the Community List and observe the sub-community badge, it still shows the old count instead of 0.

Expected behavior

After deleting a collection and all of its items, the parent community/sub-community badge count should update to reflect the correct number of remaining items/collections.

Related

Possible relevant change: Batch deletion process introduced in 10 #4570