Add image push workflow

.github/workflows/push.yaml

@@ -0,0 +1,42 @@
+name: push
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  push:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+
+      - name: Gather metadata
+        id: meta
+        uses: docker/metadata-action@v4
+        with:
+          images: registry.digitalocean.com/vatsim-containers/datafeed
+          tags: |
+            type=raw,value=latest,enable={{is_default_branch}}
+            type=sha,priority=300,prefix=
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v2
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+
+      - name: Login to DigitalOcean Container Registry
+        uses: docker/login-action@v2
+        with:
+          registry: registry.digitalocean.com
+          username: ${{ secrets.DO_REGISTRY_USERNAME }}
+          password: ${{ secrets.DO_REGISTRY_USERNAME }}
+
+      - name: Build and push
+        uses: docker/build-push-action@v4
+        with:
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          provenance: false