Issue #3418207 by longwave, fjgarlin, acbramley, mondrake, neclimdul:...

Issue #3418207 by longwave, fjgarlin, acbramley, mondrake, neclimdul: Spell-checking job fails with "couldn't find remote ref refs/heads/11.x" when 11.x branch does not exist in fork

(cherry picked from commit cdf03eab)