Log flutter version in CI build

Author: myleshorton

.github/workflows/build.yml

@@ -211,11 +211,11 @@ jobs:
           brew install imagemagick || true
 
       - name: Install Flutter
-        uses: subosito/flutter-action@v2.19.0
+        uses: subosito/flutter-action@v2.20.0
         with:
           channel: "stable"
           flutter-version-file: pubspec.yaml
-
+      - run: flutter --version
       - name: Setup JDK
         if: matrix.platform == 'android'
         uses: actions/setup-java@v4