fix(ci): checkout action

.forgejo/workflows/tests.yml

@@ -5,7 +5,9 @@ jobs:
     runs-on: alpine-plus
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        run: |
+          git clone --depth 1 \
+            http://${{ github.repository_owner }}:${{ secrets.GITHUB_TOKEN }}@${{ secrets.FORGEJO_DOMAIN }}/dot013/.mdparser
       - name: Install nix
         uses: actions/nix-quick-install-action@v27
       - name: Setup cachix