Implement Seed to generate a CODEOWNERS file and all associated records

Why?

While working on Document CODEOWNER and Approval Rule supported ... (#508172 - closed) I realised it would be a good idea to implement a database seed to test the various supported configurations of CODEOWNERS.

I'm proposing we create a development seed that will create an array of records required to test all valid and invalid configurations and also create a project with multiple branches containing different codeowner files.

We could also create merge requests that demonstrate which owners would be applied

Proposal

The seed should create a group structure following the findings from Document CODEOWNER and Approval Rule supported ... (#508172 - closed)