Update libphone number to v8.12.46 am: 16bb0e7854 am: ac6f4d4619

Original change: https://googleplex-android-review.googlesource.com/c/platform/external/libphonenumber/+/17510220

Change-Id: Ie03446d5ce1ffb7faa24ef23105ea75764d637dc
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>