We added bookworm images but didn't actually promote and tag them
because that occurs in a post merge step which cannot rely on the job
itself being updated to trigger builds. Instead we must use an explicit
change to the files we match on to trigger builds. Do that in this
change.
Change-Id: I67557f65b3417fad1ed138a57cd4a8e66dfffc2f
9b3c7ad8f0