Revert "Temporary disable dart format check on GitHub Actions"

This reverts commit b327bde.

Author: daohoangson

.github/workflows/flutter.yml

@@ -27,10 +27,7 @@ jobs:
         uses: subosito/flutter-action@44ac965b96f18d999802d4b807e3256d5a3f9fa1 # v2.16.0
         with:
           cache: true
-
-      # TODO: investigate why this fail on GitHub Actions
-      # - run: dart format --set-exit-if-changed --output none .
-
+      - run: dart format --set-exit-if-changed --output none .
       - name: Run chromedriver
         run: |
           set -e