ci: scheduled tests only on dev/master and schedules

Refs #120

.gitlab-ci.yml

@@ -35,6 +35,11 @@ default:
   extends: .check
 
 scheduled_tests_patched:
+  only:
+    refs:
+      - dev
+      - master
+      - schedules
   variables:
     R_VERSION: "patched"
   extends: .scheduled_tests