Merge "libtextclassifier: pin cpp_std to gnu++17" into main am: 0ab5782399 am: 4002d43964

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

Change-Id: I186d2d5182493ffea2e952f87e8846aeb5c5573d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>