Add GH Pages action

Author: GroovinChip

.github/workflows/gh_pages.yml

@@ -0,0 +1,17 @@
+name: Gh-Pages
+on:
+  push:
+    branches: [ dev, master ]
+  pull_request:
+    branches: [dev, master]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    
+    steps:
+      - uses: actions/checkout@v2
+      - uses: subosito/flutter-action@v1
+      - uses: erickzanardo/flutter-gh-pages@v3
+        with:
+          workingDir: example