New registry: create via YAML fails with an error

[flavio]

How to reproduce:

• Create a new Registry
• Enter the registry name: test
• Leave default registry type
• Enter the uri: ghcr.io (or anything else)
• Leave everything as default
• Click the "edit as YAML"
• Press the "Create" button

The "Create" button quickly turns red and its text changes to "Error, then it quickly transitions back to its original state.

No explanation is shown to the user.

I think this is happening because there's a validating admission controller that validates the Registry resources. The produced resource isn't providing all the requested fields, hence there's a rejection.

Expected behavior

The UI should show the rejection message coming from the validating admission controller. This is consistent with what is being done by other parts of Rancher UI when a resource is rejected by an admission controller.