Changes CI flutter version to latest version

Author: Akshatji800

.github/workflows/dart.yml

@@ -17,7 +17,7 @@ jobs:
           java-version: '12.x'
       - uses: subosito/flutter-action@v1
         with:
-          flutter-version: '3.3.4'
+          flutter-version: '3.7.11'
       - run: flutter pub get
       - run: flutter analyze
       - run: flutter format -n --set-exit-if-changed .