Remove test for -fcoroutines-ts am: 4b737c774c am: ee86e3b189

Original change: https://android-review.googlesource.com/c/platform/external/libcxx/+/2620093

Change-Id: I6d71724bec29fddaf210116d85643205ba9eceb4
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>