Fix #5533: add horizontal scroll to filtered collections report table

[guillermo-escire]

References

Fixes #5533

Description

Wraps the filtered collections report table in a scrollable container to prevent
it from being cut off when many filters are selected.

Instructions for Reviewers

List of changes in this PR:

• Wrapped the <table> in filtered-collections.component.html with a <div> with overflow-x: auto to enable horizontal scrolling.

Steps to test:

1. Go to Administration → Reports → Filtered Collections
2. Click "Select all filters"
3. Click "Show Collections"
4. Verify the table now has horizontal scroll and all columns are accessible

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