[LE unicast] Using the pairDeviceByCsip API

ag/20176285 changes the API flow.

Bug: 253541065
Test: make RunSettingsLibRoboTests ROBOTEST_FILTER=CachedBluetoothDeviceManagerTest
local test and result is on bug (pass)

Change-Id: I2354b464a93b3122b462dc9cc20556f621490d2a
1 file changed