Fix CTS failed when trigger the remote capability request to the UCE framework

While UCE framework running the initiation and had not registered the capability event listener, CTS triggerred the onRemoteCapabiluityRequest callback to the framework.
It caused that UCE framework didn't receive this callback.

Bug: 183161837
Test: atest CtsTelephonyTestCases:android.telephony.ims.cts.RcsUceAdapterTest#testOptionsRequestFromNetwork --iterations 10
Change-Id: I73328f848ef9914b2f30ee84841cc7c44a7392f3