Merge "Add FAQ about header ABI checker" into main am: 7e2c49eff3 am: fe49b03343 am: 18d2cceabb

Original change: https://android-review.googlesource.com/c/platform/development/+/2909188

Change-Id: I648641e14ad34bb81c00268e59a05c377a44ef02
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>