Fix AvrcpBipClientTest

AvrcpBipClient starts connecting at initialization, which
means during the test it will fail coonnecting and set the
connection state back to disconnected. Some tests are
setting the state directly and will fail if the connection
failure takes too long.

Added two methods connectAsync and disconnectAsync which
will call the handler and start connecting/disconnecting.
These methods are package-private as there is only one
usage of AvrcpBipClient.
Initializing AvrcpBipClient won't auto connect the device.

Bug: 297490983
Tag: #feature
Test: atest BluetoothInstrumentationTests
Change-Id: Iac68c871393e78b7a93ce149e2012d55c8cf4d41