Speedup docker builds by using cache

.github/workflows/ci.yaml

       - name: Setup BuildX
         uses: docker/setup-buildx-action@v3
 
-      - name: Setup cache
-        uses: actions/cache@v5
-        with:
-          path: /tmp/buildx-cache
-          key: ${{ runner.os }}-buildx-${{ github.sha }}
-          restore-keys: |
-            ${{ runner.os }}-buildx-
-
       - name: Login to DockerHub
         if: github.event_name != 'pull_request'
         uses: docker/login-action@v3
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Build and push
-        uses: docker/build-push-action@v2
+        uses: docker/build-push-action@v6
         with:
           pull: true
           context: .
           push: ${{ github.event_name != 'pull_request' }}
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}
-          cache-from: type=local,src=/tmp/buildx-cache
-          cache-to: type=local,dest=/tmp/buildx-cache
+          cache-from: type=gha
+          cache-to: type=gha,mode=max

Dockerfile

     ca-certificates \
     git
 
-COPY . /app
+COPY go.mod go.sum /app/
 WORKDIR /app
 
+RUN go mod download
+
+COPY . /app
+
 RUN set -x \
   && version="$(git describe --exact-match HEAD 2>/dev/null || git describe --tags --always)" \
   && go build \