chore: Add fmt check to CI (#50)

.github/workflows/ci.yaml

@@ -15,6 +15,8 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v2
+      - name: Check Format
+        run: yarn && yarn fmt:check
       - name: Login to DockerHub
         uses: docker/login-action@v1
         with:

package.json

@@ -1,6 +1,7 @@
 {
   "private": true,
   "scripts": {
+    "fmt:check": "prettier --check '**/*.{md,yaml}'",
     "fmt": "prettier --write '**/*.{md,yaml}'"
   },
   "devDependencies": {