Merge "Rewrite how to generate apexkeys.txt" into main am: aea4c9d4 am: 8fdb9fb3 am: de683620

Original change: https://android-review.googlesource.com/c/platform/build/+/2809200



Change-Id: I631064bd258754759f7a47a63c9741dcaf92d93b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>