currently there is the ability to create credentials on a job for a given reposotory or a job for a given branch in an organisation folder.
However these credentials are periodically lost.

Steps to reproduce

Create a Github Org folder that will pickup a repository in a GitHub organisation and create builds.
Run the scan so that projects and branches are created
in a job for a specific repository define a credential
update the GH org folder configuration
Run another scan so that projects are updated.

Expected Results

The credential defined on the job is still present

Actual Results

The credential defined on the job is lost

Notes: The UI currently allows the creation of the credential. the branch API has no ability no manage credentials on the job, so these could be explicitly excluded from management.

jglick believes allowing credentials to be created here is incorrect, so an alternative expectation is that credentials can not be created on jobs for repositories or their branches/PRs.