WSL VSCode setup

[smangham]

There are a few prerequisites for running VSCode in WSL:

• Install the WSL extension
• Windows 10
  • Open the WSL terminal, browse to the directory, use code . to open it
• Windows 11
• Open the code directory
• Install the Python extension (even if you already have - WSL needs a special one)
  Symptoms of it going wrong are:
• When you open a python file, and click on the interpreter in the bottom-left corner, it doesn't give you a dropdown showing your virtual environment in that directory

Given the number of people opting for WSL we should add this into the materials.