Update index.yml

Author: pritamso

articles/iot-hub/index.yml

@@ -88,7 +88,7 @@ landingContent:
      - text: Learn about Azure IoT SDKs
        url: iot-hub-devguide-sdks.md
      - text: Use the Azure IoT Tools for VS Code
-       url: https://marketplace.visualstudio.com/items?itemName=vsciot-vscode.azure-iot-tools
+       url: https://marketplace.visualstudio.com/items?itemName=vsciot-vscode.azure-iot-toolkit
      - text: Supported device protocols
        url: iot-hub-devguide-protocols.md