Remove Microsoft Learn reference from intro tutorial

Microsoft Learn integration is not implemented in the tutorials.
Only Google Colab links are available at the top of tutorial pages.
This updates the documentation to reflect the actual functionality.

Fixes #3678

Author: patrocinio

beginner_source/basics/intro.py

@@ -34,7 +34,7 @@
 -------------------------
 You can run this tutorial in a couple of ways:
 
-- **In the cloud**: This is the easiest way to get started! Each section has a "Run in Microsoft Learn" and "Run in Google Colab" link at the top, which opens an integrated notebook in Microsoft Learn or Google Colab, respectively, with the code in a fully-hosted environment.
+- **In the cloud**: This is the easiest way to get started! Each section has a "Run in Google Colab" link at the top, which opens an integrated notebook in Google Colab with the code in a fully-hosted environment.
 - **Locally**: This option requires you to setup PyTorch and TorchVision first on your local machine (`installation instructions <https://pytorch.org/get-started/locally/>`_). Download the notebook or copy the code into your favorite IDE.