ci: replace no-cache with GHA cache + remove Docker Hub login (CAR-272, CAR-273)

Co-Authored-By: Paperclip <noreply@paperclip.ing>

.github/workflows/ci.yml

@@ -70,12 +70,6 @@ jobs:
           echo "version=$VERSION" >> "$GITHUB_OUTPUT"
           echo "CalVer tag: $VERSION"
 
-      - name: Log in to Docker Hub
-        uses: docker/login-action@v3
-        with:
-          username: ${{ secrets.DOCKERHUB_USERNAME }}
-          password: ${{ secrets.DOCKERHUB_TOKEN }}
-
       - name: Log in to GHCR
         if: github.event_name == 'push' && github.ref == 'refs/heads/main'
         uses: docker/login-action@v3
@@ -102,7 +96,8 @@ jobs:
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}
           target: prod
-          no-cache: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
 
       - name: Create git tag
         if: github.event_name == 'push' && github.ref == 'refs/heads/main'