edit-util: do not try to recreate temp file if missing

edit-util: do not try to recreate temp file if missing

We initially read from temp file, then strip it, and write
back to it. If the file suddenly disappeared during the process,
it indicates someone else is touching our temp file
behind our back. Let's not silently continue.

(cherry picked from commit 3b5b2ff8fa6413afc2e5a058ea8281a58a4c691d)