[FEATURE] Set spec.source.type as mandatory field

[qu1queee]

Is there an existing feature request for this?

• 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.

On making source.type mandatory.

The main reason, is that users are not used to define a type(e.g. oci, git), but just the source object definition. In the absence of the type definition, a buildrun will never succeed.

Describe alternatives you have considered.

None

Anything else?

In the future, we could make this something that a mutating webhook could handle(setting the type depending on the source type), changing the proposed behaviour.