Context configuration file misnamed

[helendduncan]

✅ Checklist

• I have searched open and closed issues for duplicates
• This is a request for a change to documentation
• This isn't a feature request or bug report
• This isn't an open-ended question (open a discussion if it is).

📒 Where is the problem?

Deployment docs "Set up context" page say the context configuration file is called context.yaml, when it is actually contexts.yaml.
It also doesn't give the path of the file, which might make it seem like the file should be in $PWD.

We should correct the file name, or perhaps remove it if we think users don't need this detail.

We could add a block which gives the path for the file on Linux/MacOS/Windows.

📝 Required documentation changes