Fix "Clear" button when swapping between drawer searches

After applying a checkbox(es) on a nuxeo-search-form layout accessed from a Drawer item and navigating to a different search to do the same, upon returning to the first layout the Clear button fails to reset the checkboxes.

Steps to Reproduce:

1. Navigate to the default Search from the left-hand Drawer
2. Apply 1+ checkbox aggregates (for example "Last 24h" under Modification Date)
3. Navigate to Assets search from Drawer
4. Apply 1+ checkbox aggregates (for example "Picture" under Asset Type)
5. Navigate back to default Search
6. Click the "CLEAR" button at the bottom of the form

Expected result: the nuxeo-checkbox-aggregation elements are cleared

Actual result: the nuxeo-checkbox-aggregation elements are not cleared. The button only clears the checkboxes after applying new filter settings, or returning to Asset search and clicking the "CLEAR" button there (upon returning to default Search, the form automatically clears).

(see attached video)