Release/v2 1

[luke-hill]

Summary

Update changelog (Cut v2.1)

Details

As written above

Motivation and Context

Not had a cut in 9 months, this will be a cut that also enables cucumber4 and removes ruby 2.3

How Has This Been Tested?

Doc update so N/A

Screenshots (if appropriate):

Types of changes

N/A

Checklist:

• [ ] I've added tests for my code.
• [ ] My change requires a change to the documentation.
• [x] I have updated the documentation accordingly.

[luke-hill]

Can we merge this if we're happy. If there is anything you want re-wording feel free to prod me and I'll fix this today/tomorrow