Remove unuseful verification to the PackageMonitor migration

In PackageMonitor, it is no longer based on broadcast receivers to
listen package added/removed/... events. Therefore the verification
should be removed.

Bug: 341882646
Flag: TEST_ONLY
Test: atest com.android.systemui.controls.controller.PackageUpdateMonitorTest
Change-Id: Id00a940bc5c2f8a9ac395163773e00ac2878d6ed