Temporarily exclude `JniCompilerTests` from the ART MTS definition. am: f53fa282cc am: 39091af211 am: 580e85a249 am: dabe6d2d7d am: d18fe8b332

Original change: https://android-review.googlesource.com/c/platform/art/+/2218043

Change-Id: Id320d322d4397ad5f85f964394ab6680cfd82eb6
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>