A few weeks ago, GitHub announced that they added an API for managing default setup Code Scanning on a repository.. This would be useful for our Terraform, and step 1 is adding it here. I'll pick this up if I get a chance, but if someone beats me to it, feel free.

https://docs.github.com/en/rest/code-scanning?apiVersion=2022-11-28#get-a-code-scanning-default-setup-configuration
https://docs.github.com/en/rest/code-scanning?apiVersion=2022-11-28#update-a-code-scanning-default-setup-configuration