Enable the Pbap Client authenticator

The authentication framework uses the service declaration in the
manifest to allow us create accounts for connected devices. The service
must be enabled for it register in their framework. In our case as well,
it doesn't seem like the service ever actually get's started either.
Just existing in the manifest is enough for us to create the accounts we
need to.

Before this change, it was disabled and PBAP would enable it when it
started. It was found that there's latency between when the service
manifest change is written and when the authentication framework picks
up and acts on the change such that we can create accounts. This causes
a race condition between when they've processed our manifest change such
that we can create an account, and we actually try to make an account.
Making an account without the auth framework knowning of our change
causes crashes.

Given there's no easy way for us to know when the auth framework is
ready for us, the easiest way to handle this is the leave the component
enabled.

Tag: #stability
Bug: 229629444
Test: atest BluetoothInstrumentationTests
Merged-In: If0af12607dbb7a910013f4d9171b70662f0e6319
Change-Id: If0af12607dbb7a910013f4d9171b70662f0e6319