Add UT for updated remote connection service tracking.

We updated the process for how associated call counts are tracked for remote connection services as part of ag/25400744. This CL increases our test coverage of that change.

Fixes: 314844878
Test: atest CreateConnectionProcessorTest#testConnectionManagerConnectionServiceSuccess
Flag: com.android.server.telecom.flags.updated_rcs_call_count_tracking
Change-Id: Ia3ed5e363406509fc3ed8959e6b2bac674e7fcb6