Merge "Set up libtextclassifier_tests into MTS" into rvc-dev am: 0bce29a225 am: be3c7b5e56

Original change: https://googleplex-android-review.googlesource.com/c/platform/external/libtextclassifier/+/11685296

Change-Id: Ic8466110d37aecf2e37aa79b9a8ad2d90acac78a