le_audio: Handle re-configuration case while sink monitoring

While monitoring sink stream and re-configuration happens there are two
possibilities: new configuration would be bi-directional (with sink), or
uni-directional (without sink). If new configuration would be
uni-directional (without sink) a stream suspended notification should be
send to service.

Tag: #feature
Test: atest bluetooth_le_audio_client_test
Bug: 298080973
Bug: 308171251
Change-Id: Ib9ac4ec1e4ca8e4da67217045e0321604c1d3266