Broken link fixed

Author: pritamso

articles/iot-fundamentals/toc.yml

@@ -73,7 +73,7 @@
   - name: Azure Roadmap
     href: https://azure.microsoft.com/roadmap/?category=iot
   - name: Azure IoT Tools for VS Code
-    href: https://marketplace.visualstudio.com/items?itemName=vsciot-vscode.azure-iot-tools
+    href: https://marketplace.visualstudio.com/items?itemName=vsciot-vscode.azure-iot-toolkit
   - name: Azure IoT Explorer tool
     href: https://github.com/Azure/azure-iot-explorer
   - name: iothub-diagnostics tool