Update kotlinc to 1.7.20 am: 4e3c9ce7ac am: 2383925909

Original change: https://android-review.googlesource.com/c/platform/external/kotlinc/+/2055028

Change-Id: Iad80c49783912c62f6fc15ef13fe3cb7c68dc44f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>