Add scheduled update in .gitlab-ci.yml file

.gitlab-ci.yml

@@ -5,6 +5,7 @@ variables:
 
 stages:
   - build
+  - pull_upstream
 
 image_build:
   stage: build
@@ -14,4 +15,36 @@ image_build:
   script: |
     CI_COMMIT_SHA_7=$(echo $CI_COMMIT_SHA | cut -c1-7)
     docker build --tag $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA_7 .
-    docker push $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA_7
\ No newline at end of file
+    docker push $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA_7
+
+pull_jupytext_github:
+  stage: pull_upstream
+  script: |
+    whoami
+    printenv
+    CI_PUSH_REPO=$(echo $CI_REPOSITORY_URL | perl -pe 's#.*@(.+?(\:\d+)?)/#git@\1:#')
+    git remote set-url --push origin "${CI_PUSH_REPO}"
+    git config user.name "Gitlab CI"
+    git config user.email "tokenowner@email.com"
+
+    # runner runs on a detached HEAD, create a temporary local branch for editing
+    git checkout -b ci_processing
+    
+    # update jupytext submodule
+    git submodule foreach git pull origin main
+    git add jupytext
+    git commit -m "sync: jupytext@$(git submodule status | sed 's/^ *//' | head -c8)"
+
+    # push changes
+    # always return true so that the build does not fail if there are no changes
+    git push origin ci_processing:${CI_BUILD_REF_NAME} || true
+
+
+  only:
+    refs:
+      - schedules
+    variables:
+      - $SCHEDULE_TYPE == "check_upstream"
+  allow_failure: false
+
+