Send request immediately to handler

The following methods are updated in this cl:
- requestNtnSignalStrength
- requestSatelliteSubscriberProvisionStatus
- setNtnSmsSupportedByMessagesApp

Bug: 409584433
Test: atest
Flag: com.android.internal.telephony.flags.satellite_improve_multi_thread_design
Change-Id: I764f3b178dab25dd6a03c90782d5ca12ecf6adfc