[FEATURE] Document usage of OCIArtifact source type

[qu1queee]

Is there an existing feature request for this?

• [X] I have searched the existing feature requests

Is your feature request related to a problem or use-case? Please describe.

Use case

Describe the solution that you would like.

Extend this Build doc to document how to use the OCIArtifact source type.

Describe alternatives you have considered.

None.

Anything else?

No.