Add action for syntax checking

.github/workflows/syntax-checking.yml

@@ -0,0 +1,18 @@
+name: syntax-checking
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: 'Yamllint'
+      uses: karancode/yamllint-github-action@master
+      with:
+        yamllint_strict: false
+        yamllint_comment: true