CI: Fix initial creation of comment in unmapped_rules check
What does this MR do?
Followup to !598 (merged) / b0bb3649 to handle the case where there is no existing comment. Currently this fails due to the array being nil
.
What are the relevant issue numbers?
gitlab-org/gitlab#461799 (closed)
Does this MR meet the acceptance criteria?
N/A, CI only
Edited by Julian Thome