Create sync-with-upstream.yml

.github/workflows/sync-with-upstream.yml

@@ -0,0 +1,33 @@
+name: Sync with Upstream
+
+on:
+  schedule:
+    - cron: '25 0 * * *' # 매일 자정(UTC 기준)에 실행
+  workflow_dispatch:
+
+jobs:
+  sync:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout forked repository
+      uses: actions/checkout@v2
+      with:
+        persist-credentials: false
+
+    - name: Configure git
+      run: |
+        git config --global user.name 'keinn51'
+        git config --global user.email '[email protected]'
+
+    - name: Add remote upstream
+      run: git remote add upstream https://github.com/42-seoul-projects-kyungsle/bundle-repo.git
+
+    - name: Fetch changes from upstream
+      run: git fetch upstream
+
+    - name: Merge changes from upstream/main to main
+      run: |
+        git checkout main
+        git merge upstream/main --allow-unrelated-histories
+        git push https://${{ secrets.GH_PAT }}@github.com/keinn51/bundle-repo-42-seoul-projects.git main