[ci] Disable for non-MR user-scoped pipelines.

.gitlab-ci.yml

@@ -21,8 +21,16 @@ variables:
   BUILD_TESTS: "true"
   BUILD_CTEST: "true"
 
+workflow:
+  rules:
+    # Disable CI for non-MR user-scoped pipelines
+    - if: '$CI_MERGE_REQUEST_IID == null && $CI_PROJECT_NAMESPACE != "ogs"'
+      when: never
+    - if: $CI_MERGE_REQUEST_IID                    # merge requests
+    - if: $CI_COMMIT_TAG                           # tags, ogs/ogs repo only
+    - if: $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH  # master, ogs/ogs repo only
+
 include:
-  - template: 'Workflows/MergeRequest-Pipelines.gitlab-ci.yml'
   - template: 'Code-Quality.gitlab-ci.yml'
   # extends
   - local: '/scripts/ci/extends/defaults.yml'