SAP: Ensure pending intent is immutable am: 7b17763dad am: 025e223f5d am: 927b9b73d1 am: bbbd808b95

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Bluetooth/+/12215764

Change-Id: I247f6e29e0d83fede42e666dd67a8538dc8f54c6