Merge "libtextclassifier: pin cpp_std to gnu++17" into main am: 0ab5782399

Original change: https://android-review.googlesource.com/c/platform/external/libtextclassifier/+/2833010

Change-Id: Iee418a19b20ac04445a1376fd83d875ce1cc910a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>