Updating installed extensions section of README.md (#22893)

Adding the Python Debugger to the installed extensions section of the
README.

Author: cwebster-99

README.md

@@ -9,9 +9,12 @@ The Python extension does offer [some support](https://github.com/microsoft/vsco
 
 ## Installed extensions
 
-The Python extension will automatically install the [Pylance](https://marketplace.visualstudio.com/items?itemName=ms-python.vscode-pylance) extension to give you the best experience when working with Python files. However, Pylance is an optional dependency, meaning the Python extension will remain fully functional if it fails to be installed. You can also [uninstall](https://code.visualstudio.com/docs/editor/extension-marketplace#_uninstall-an-extension) it at the expense of some features if you’re using a different language server.
+The Python extension will automatically install the following extensions by default to provide the best Python development experience in VS Code:
 
-Extensions installed through the marketplace are subject to the [Marketplace Terms of Use](https://cdn.vsassets.io/v/M146_20190123.39/_content/Microsoft-Visual-Studio-Marketplace-Terms-of-Use.pdf).
+- [Pylance](https://marketplace.visualstudio.com/items?itemName=ms-python.vscode-pylance) - to provide performant Python language support
+- [Python Debugger](https://marketplace.visualstudio.com/items?itemName=ms-python.debugpy) - to provide a seamless debug experience with debugpy
+
+These extensions are optional dependencies, meaning the Python extension will remain fully functional if they fail to be installed. Any or all of these extensions can be [disabled](https://code.visualstudio.com/docs/editor/extension-marketplace#_disable-an-extension) or [uninstalled](https://code.visualstudio.com/docs/editor/extension-marketplace#_uninstall-an-extension) at the expense of some features. Extensions installed through the marketplace are subject to the [Marketplace Terms of Use](https://cdn.vsassets.io/v/M146_20190123.39/_content/Microsoft-Visual-Studio-Marketplace-Terms-of-Use.pdf).
 
 ## Quick start
 

build/license-header.txt

@@ -1,7 +1,7 @@
 PLEASE NOTE: This is the license for the Python extension for Visual Studio Code. The Python extension automatically installs other extensions as optional dependencies, which can be uninstalled at any time. These extensions have separate licenses:
 
- - The Jupyter extension is released under an MIT License:
-  https://marketplace.visualstudio.com/items/ms-toolsai.jupyter/license
+ - The Python Debugger extension is released under an MIT License:
+  https://marketplace.visualstudio.com/items/ms-python.debugpy/license
 
  - The Pylance extension is only available in binary form and is released under a Microsoft proprietary license, the terms of which are available here:
   https://marketplace.visualstudio.com/items/ms-python.vscode-pylance/license