add sync repo action

.github/workflows/sync_repos.yml

@@ -0,0 +1,29 @@
+name: sync repos
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  clone-and-push:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v2
+
+      - name: Clone GitHub repository
+        run: |
+          git clone --mirror https://github.com/ok-oldking/ok-wuthering-waves.git
+          cd ok-wuthering-waves.git
+
+      - name: Set up Git credentials
+        run: |
+          git config --global user.name "${{ secrets.CODING_USERNAME }}"
+          git config --global user.password "${{ secrets.CODING_PASSWORD }}"
+
+      - name: Push to Coding.net
+        run: |
+          git remote add coding https://e.coding.net/g-frfh1513/ok-wuthering-waves/ok-wuthering-waves.git
+          git push --mirror coding --force