[Audiosharing] Block pairing during audio sharing

When a) there are two sinks in sharing b) there is at least one temp
bond device connected

Test: atest
Flag: com.android.settingslib.flags.enable_temporary_bond_devices_ui
Bug: 392004799
Change-Id: Id093b4c0b67bdc1db621e0241e79900abbd26c0f