Automatic sync with Gitlab's read-only mirror

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

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+name: Automatic sync with Gitlab's read-only mirror
+
+on: [workflow_dispatch, push]
+
+jobs:
+  mirror:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up SSH key for Runner
+        env:
+          SSH_KEY: ${{ secrets.GITLAB_DEPLOY_KEY }}
+        run: |
+          mkdir -p ~/.ssh
+          echo "$SSH_KEY" > ~/.ssh/id_ed25519
+          chmod 600 ~/.ssh/id_ed25519
+          ssh-keyscan -t rsa github.com >> ~/.ssh/known_hosts
+          ssh-keyscan -t rsa gitlab.com >> ~/.ssh/known_hosts
+
+      - name: Clone repository from GitHub as mirror and push to Gitlab
+        env:
+          REPO_ORIGINAL: "https://github.com/rehlds/hitboxtracker.git"
+          REPO_TARGET:   "git@gitlab.com:rehlds/hitboxtracker.git"
+        run: |
+          git clone --mirror "$REPO_ORIGINAL" repo-mirror
+          cd repo-mirror
+          git remote set-url origin "$REPO_TARGET"
+          git push --mirror --force