main/postmarketos-ui-phosh: enable app drawer filtering

Was 5 years ago disabled because most apps weren't marked as adaptive. But that clearly has changed today and remaining apps should be updated upstream.

That means that some apps might "disappear" when existing installations had un-adaptive apps, but given the button on the button that is easy to read, I consider that fine.

This reverts commit ae02ad91 ("main/postmarketos-ui-phosh: disable app drawer filtering (MR 2298)")