internal/ci: enforce Signed-off-by temporarily
Until Gerrit fixes the bug where it does not apply the restriction to
admin accounts.
Change-Id: Iadf68723367aa06798aa2b54d8d1eecf68e5b12a
Signed-off-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/537156
Reviewed-by: Paul Jolly <paul@myitcv.io>