The Dart-Code plugin suggests to install the Google Arb editor even so it is already installed #5509

Describe the bug
When opening an arb file, e. g. the app_en.arb file for the Flutter UI Internalization feature, the Dart-Code plugin suggests to install the Google arb editor even so it is already installed by showing a message box with the message "The Google ARB Editor extension can provide validation and completion for ARB files.". When clicking the "Install Google.arb-editor" button, a box is shown permanently that displays "Installing Google.arb-editor" until the Visual Studio Code window is closed.

To Reproduce
Steps to reproduce the behavior:

1. Ensure you have the Google Arb editor installed,
2. Checkout the repository https://github.com/flutter/website.git ,
3. Open the subpath examples/internationalization/gen_l10n_example in Visual Studio Code,
4. Open the file "lib/l10n/app_en.arb",
5. The Dart Code plugin will now suggest to install the Google arb editor.

Expected behavior
The expected behavior is that the Dart Code plugin checks that the Google arb editor extension is not yet installed before suggesting to install it.

Screenshots
I think the description above describes the problem reproducibly.

Please complete the following information:

You can run the Dart: Collect Diagnostic Information command from the VS Code command palette (F1) to easily capture this information or provide it manually.

• Operating System and version: Windows 11 Pro 24H2
• VS Code version: win 1.99.3
• Dart extension version: 3.110.0
• Dart/Flutter SDK version: 3.7.0, 3.29.0
• Target device (if the issue relates to Flutter debugging): -