Catch and ignore `IllegalArgumentException` thrown by `unbindService`

When `TransportConnection` handles `onServiceConnected` or
`onBindingDied` it calls `Context.unbindService`. In a very small number
of cases this fails because the connection is not (or no longer?)
registered. When this happens, the system server crashes causing the
device to reboot. We don't really care if the service is not registered
when we try to unbind it, so we just catch and ignore the exception to
avoid crashing the system server.

Bug: 335547110
Test: atest TransportConnectionTest.java
Change-Id: Ic7f34eacd1f621c42a68128ef992043dba6808f1