Update mkdocs.yml

Include debugging page about VSC now that it has merged into the code

Author: Amanda Butler

mkdocs.yml

@@ -57,6 +57,7 @@ pages:
 - ['debugging/Keil.md', 'Debugging', 'Debugging with uVision 5']
 - ['debugging/debugging_eclipse_pyocd.md', 'Debugging', 'Debugging with Eclipse']
 - ['debugging/other_ides.md', 'Debugging', 'Debugging with other IDEs']
+- ['debugging/vscode.md', 'Debugging', 'Debugging with Visual Studio Code']
 - ['debugging/debugging_microbit.md', 'Debugging', 'Debugging the BBC micro:bit']
 
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