ci: skip MacOS tests in security repo

.gitlab-ci.yml

@@ -157,6 +157,12 @@ build:darwin:
       - $SKIP_CI == "1"
       - $SKIP_TRAVIS == "1"
   when: delayed
+  except:  # trigger job only in repos under our control
+    refs:
+      - master
+      - branches@knot/security/knot-resolver
+    variables:
+      - $SKIP_CI == "1"
   start_in: 3 minutes  # give the build in Travis CI time to finish
   script:
     - ci/travis.py ${CI_COMMIT_REF_NAME}