Don't panic if no certificates found am: b7550aa0 am: 3495c736 am: e3082c62 am: 68f2f321

Original change: https://android-review.googlesource.com/c/platform/build/soong/+/2596605



Change-Id: Ib2c828aee631acedab17b6c0e014a95650a2c45f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>