[gnome-shell] ci/check-commit-log: Reverse the merge request URL check

[Marge Bot <marge-bot src gnome org>]

commit 5f7615d3fcc7d9b737439b60237e6f20e6f47d24
Author: Jonas Ådahl <jadahl gmail com>
Date:   Fri Nov 6 17:59:28 2020 +0100

    ci/check-commit-log: Reverse the merge request URL check
    
    Instead of making sure there is a reference to a bug or merge request,
    make sure there isn't. The reason for this is that marge-bot will always
    append a merge request URL in the end of the commit message.
    
    Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1491>

 .gitlab-ci/check-commit-log.sh | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/.gitlab-ci/check-commit-log.sh b/.gitlab-ci/check-commit-log.sh
index 8d0e2ee039..5a469328d6 100755
--- a/.gitlab-ci/check-commit-log.sh
+++ b/.gitlab-ci/check-commit-log.sh
@@ -16,16 +16,16 @@ if [ -z "$commits" ]; then
   exit 1
 fi
 
-function commit_message_has_url() {
+function commit_message_has_mr_url() {
   commit=$1
   commit_message=$(git show -s --format='format:%b' $commit)
-  echo "$commit_message" | grep -qe 
"\($CI_MERGE_REQUEST_PROJECT_URL/\(-/\)\?\(issues\|merge_requests\)/[0-9]\+\|https://bugzilla.gnome.org/show_bug.cgi?id=[0-9]\+\)"
+  echo "$commit_message" | grep -qe 
"^$CI_MERGE_REQUEST_PROJECT_URL\/\(-\/\)\?merge_requests\/$CI_MERGE_REQUEST_IID$"
   return $?
 }
 
 for commit in $commits; do
-  if ! commit_message_has_url $commit; then
-    echo "Missing merge request or issue URL on commit $(echo $commit | cut -c -8)"
+  if commit_message_has_mr_url $commit; then
+    echo "Commit $(echo $commit | cut -c -8) message must not contain a link to its own merge request"
     exit 1
   fi
 done