Add JSON workflow at GitHub Actions

Author: tmknom

.github/workflows/json.yml

@@ -0,0 +1,14 @@
+name: JSON
+on:
+  pull_request:
+
+jobs:
+  format:
+    name: Format
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    steps:
+      - name: Checkout
+        uses: actions/[email protected]
+      - name: Prettier
+        run: docker run --rm -v ${PWD}:/work tmknom/prettier --list-different --parser=json '**/*.json'