Add missing cache param to docker build action

Signed-off-by: trivernis <trivernis@protonmail.com>

.github/workflows/docker.yml

@@ -42,5 +42,7 @@ jobs:
           file: ./Dockerfile
           platforms: ${{github.events.inputs.platforms}}
           push: true
+          cache-from: type=local,src=/tmp/.buildx-cache
+          cache-to: type=local,dest=/tmp/.buildx-cache
           tags: |
             trivernis/snekcloud-server:alpine