Merge branch 'fix_undercoverage_not_existing_in_old_branches' into 'master'

Fix undercoverage not existing in older branches

See merge request gitlab-org/gitlab!75700

.gitlab/ci/rails.gitlab-ci.yml

@@ -537,7 +537,9 @@ rspec:undercoverage:
       else
         echo "Using \$CI_COMMIT_SHA ($CI_COMMIT_SHA) for this non-merge result pipeline.";
       fi;
-    - run_timed_command "scripts/undercoverage"
+    - if [ -f scripts/undercoverage ]; then
+        run_timed_command "scripts/undercoverage";
+      fi;
 
 rspec:feature-flags:
   extends: