login using action

.gitea/workflows/build.yml

@@ -18,12 +18,12 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
 
-      - name: Login to Registry
-        run: |
-          echo "${{ secrets.REGISTRY_PASSWORD }}" | docker login \
-            ${{ secrets.REGISTRY_HOST }} \
-            -u "${{ secrets.REGISTRY_USERNAME }}" \
-            --password-stdin
+      - name: Log in to Gitea Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ github.server_url }}
+          username: ${{ secrets.CI_USER }}
+          password: ${{ secrets.CI_PASSWORD }}
 
       - name: Make build script executable
         run: chmod +x build-and-copy.sh