Reclassify OFL as notice per cl/537072410 am: 7f1841380b

Original change: https://android-review.googlesource.com/c/platform/external/google-fonts/zilla-slab/+/2611895

Change-Id: I5d17600e9978dc3cc49ca3835894378d28382dd3
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>