[actions] use actions/checkout@v3 instead of git clone

.gitea/workflows/build-sporq.yaml

@@ -12,8 +12,8 @@ jobs:
         run: python3 -m pip install --user qmk
       - run: echo "${HOME}/.local/bin" >> $GITHUB_PATH
 
-      - name: Set up Git repository
-        run: git clone --depth 1 https://git.sporq.de/sporq/qmk-firmware.git qmk-firmware
+      - name: Checkout
+        uses: actions/checkout@v3
 
       - name: Set up QMK
         working-directory: .qmk-firmware