format yaml file properly

.github/workflows/mobile.js.yml

@@ -5,15 +5,13 @@ name: Node.js CI
 
 on:
   push:
-    branches: [ "master" ]
+    branches: ['master']
   pull_request:
-    branches: [ "master" ]
+    branches: ['master']
 
 jobs:
   build:
-
     runs-on: ubuntu-latest
-
     strategy:
       matrix:
         node-version: [12.x, 14.x, 16.x]
@@ -22,7 +20,6 @@ jobs:
     steps:
       - uses: actions/checkout@v3
       - name: Use Node.js ${{ matrix.node-version }}
-      working-directory: ./mobile-ui
         uses: actions/setup-node@v3
         with:
           node-version: ${{ matrix.node-version }}