Description of the Change

While implementing tests I discovered an issue where it wasn't possible to clear the Facet by Range filter, as adjusting the range to the full range was still applying a filter for any posts with that custom field. This PR adds a Clear link to the Facet by Meta Range block which clears the range filter entirely.

How to test the Change

1. Add the Facet by Meta Range block.
2. View an archive of posts with some posts containing the field used for the range, and some not. All posts should be displayed.
3. Apply the range filter without any changes. Only posts with the field should be show.
4. A clear link should appear on the Facet by Meta Range block. Clicking it should show all posts again.

Changelog Entry

N/A.

Credits

Props @JakePT

Checklist:

• I agree to follow this project's Code of Conduct.
• I have updated the documentation accordingly.
• I have added tests to cover my change.
• All new and existing tests pass.