feat(slack-notification): Add slack notification

.github/workflows/main.yml

@@ -2,7 +2,7 @@ name: CI
 
 on:
   push:
-    branches: [ master, github-action ]
+    branches: [ master, github-action-slack-notification ]
   pull_request:
     branches: [ master ]
 
@@ -43,3 +43,13 @@ jobs:
       env:
         COVERALLS_REPO_TOKEN: ${{ secrets.GITHUB_TOKEN }}
       run: vendor/bin/php-coveralls -v
+    - name: Notification
+      if: always()
+      id: slack
+      uses: wingify/slack-github-action@v1.15.1-wingify
+      with:
+        channel-id: "fs-review-team"
+        slack-message: "<!here> Test on *PHP-${{ matrix.php-version }}* and *${{ matrix.operating-system }}* got *${{job.status}}* ${{job.status == 'success' && ':heavy_check_mark:' || ':x:'}} \nCommit: `${{github.event.head_commit.message}}`. \nCheck the latest build: https://github.com/wingify/vwo-php-sdk/actions"
+        color: "${{job.status == 'success' && '#00FF00' || '#FF0000'}}"
+      env:
+        SLACK_BOT_TOKEN: ${{ secrets.SLACK_NOTIFICATIONS_BOT_TOKEN }}