Remove old footer actions implementation

This CL removes the old implementation of the QS footer actions. The new
implementation was turned on in http://ag/20139744 and didn't cause any
regression.

The tests that were removed in this CL are test cases that are already
tested in FooterActionsViewModelTest or FooterActionsInteractorTest.

Bug: 242040009
Test: atest QSFragmentTest
Test: atest QSSecurityFooterTest
Test: atest FooterActionsViewModelTest
Test: atest FooterActionsInteractorTest
Change-Id: I88413727a5f6ca37deea6333c411c1b9b7bffeeb