setup fmt checks

.github/workflows/deno.yml

@@ -0,0 +1,28 @@
+# For more information see: https://github.com/denoland/setup-deno
+
+name: Deno
+
+on:
+  push:
+    branches: ["main"]
+  pull_request:
+    branches: ["main"]
+
+permissions:
+  contents: read
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Setup repo
+        uses: actions/checkout@v3
+
+      - name: Setup Deno
+        uses: denoland/setup-deno@004814556e37c54a2f6e31384c9e18e983317366
+        with:
+          deno-version: v1.23.1
+
+      - name: Verify formatting
+        run: deno fmt --check