Update backend

Author: renovate[bot]

.github/workflows/deploy.yaml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
       - name: Login to Docker registry
         uses: docker/login-action@v3
         with:
@@ -19,7 +19,7 @@ jobs:
           password: ${{ secrets.DOCKER_REGISTRY_PASSWORD }}
       - name: Build and push
         id: docker_build
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         with:
           push: true
           tags: postmodern.alexdaniel.org/alexdaniel-backend:${{ github.sha }} ${{ github.ref == 'refs/heads/main' && ', postmodern.alexdaniel.org/alexdaniel-backend:latest' || '' }}