Add debug logs to understand update start delay am: 6bec1eda3d am: 6384af1058

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/3167416

Change-Id: I6f5b33dd3560afbc04dbd7d3ef782e6b7d7b6cc9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>