update workflow to use proper actions

.gitea/workflows/nightly-build.yml

@@ -8,13 +8,25 @@ on:
 jobs:
   build-and-push:
     container:
-      image: alpine:latest
+      image: docker:dind
     steps:
-      - name: Install dependencies
+      - name: Set up Docker Buildx
-        run: apk add docker nodejs
+        uses: docker/setup-buildx-action@v3
+      - name: Set up QEMU (for cross-platform builds)
+        uses: docker/setup-qemu-action@v3
       - name: Login to Docker registry
-        run: docker login git.arinity.org -u matt -p "${{ secrets.DOCKER_PUSH_TOKEN }}"
+        uses: docker/login-action@v3
+        with:
+          registry: git.arinity.org
+          username: matt
+          password: ${{ secrets.DOCKER_PUSH_TOKEN }}
       - name: Checkout repository
         uses: actions/checkout@v4
-      - name: Build & Push Docker image
+      - name: Build and push image
-        run: docker build --push --no-cache -t git.arinity.org/meshsense-tools/meshsense:nightly .
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: ./Dockerfile
+          platforms: linux/amd64,linux/arm64
+          push: true
+          tags: git.arinity.org/meshtastic-tools/meshsense:nightly