Pass platform param.

Author: csasarak

.github/workflows/build-docker.yml

@@ -50,7 +50,7 @@ jobs:
       - name: Build and push
         uses: docker/build-push-action@v6
         with:
-          platforms: linux/amd64,linux/arm64
+          platforms: ${{ matrix.platform }}
           file: ${{ format('./{0}/Dockerfile', matrix.ghc-version) }}
           push: false # ${{ github.ref == 'refs/heads/master' }}
           tags: ${{ format('{0}:{1}', env.IMAGE_NAME, matrix.ghc-version) }}