cerbero: Allow fetch-cache to fetch an older cache
Check that the commit is an ancestor of the current HEAD revision, and if so, accept it. This avoids hosing the CI whenever a cerbero commit is pushed.
CC: @ndufresne
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Check that the commit is an ancestor of the current HEAD revision, and if so, accept it. This avoids hosing the CI whenever a cerbero commit is pushed.
CC: @ndufresne