[web] Use hook instead of connect function in FilterPanel

Test Plan: Checked if the filter panel still showed up, and functions such as filtering, clear filter, and include deleted items still worked

Reviewers: palys-swm, ashoat, atul

Reviewed By: ashoat

Subscribers: ashoat, KatPo, zrebcu411, Adrian, atul

Differential Revision: https://phabricator.ashoat.com/D818