Discard on-going steps for domain selection on local hangup

If the user disconnects the call, then on-going steps can be
executed asynchronously for domain selection should be discarded
to avoid potential abnormal behavior.

Bug: 243344927
Test: atest TelephonyConnectionServiceTest
Change-Id: I1eece8955da8669c9f3458c35b24ec1558fd1abe
2 files changed