Add multiple platform support

.github/workflows/main.yaml

@@ -4,21 +4,16 @@ on:
       - "*"
 
 jobs:
-  build:
-    name: Build, push
+  docker-buildx:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout main
         uses: actions/checkout@main
 
-      - name: Build container
-        run: docker build --tag gwhittington/meshtastic-bridge:latest .
-
-      - name: Log in to Container Registry with short-lived credentials
-        run: docker login --username=gwhittington --password "${{secrets.DOCKER_HUB}}"
-
-      - name: Push image to Container Registry
-        run: docker push gwhittington/meshtastic-bridge:latest
-
-      - name: Logout from Container Registry
-        run: docker logout
+      - name: Build and publish image
+        uses: zmingxie/docker_buildx@master
+        with:
+          publish: true
+          imageName: gwhittington/meshtastic-bridge:latest
+          dockerHubUser: gwhittington
+          dockerHubPassword: ${{secrets.DOCKER_HUB}}