Enable layer caching with 'cache-mode: max'

This resolves #167 (comment).

Author: gy-mate

.github/workflows/docker-publish.yml

@@ -24,6 +24,8 @@ jobs:
       push: true
       platforms: linux/amd64,linux/arm64
       build-args: OVERPASS_VERSION=${{ github.event.release.tag_name || inputs.overpass_version }}
+      cache: true
+      cache-mode: max
       meta-images: ${{ vars.DOCKERHUB_USERNAME }}/overpass-api
       meta-tags: type=semver,pattern={{version}}
     secrets: