Fix issue that duplicate the missed call notification

Prevents duplicate adding UserHandle that are evacuated to deferring
the display of missed call notifications until boot completed.

Test: manual
Test: auto - Passed TelecomUnitTests#MissedCallNotifierImplTest
Bug: 218628432

Change-Id: Ia4a3a416111daa7c9025040946a55f19c3cc9590
1 file changed