Added github action for CI. (#9)

.github/workflows/ci.yaml

@@ -0,0 +1,25 @@
+name: Continuous Integration
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  tests:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Start xvfb
+      run: /usr/bin/Xvfb :99 -screen 0 1024x768x24 > /dev/null 2>&1 &
+
+    - name: install nodejs dependencies
+      run: npm install
+
+    - name: compile the project
+      run: npm run compile
+
+    - name: Test the extension via shell script
+      run: bash tests/e2e.sh