Remove .json files (kube-schema.json, validation-schema.json, $$$extension.json)

[manusa]

Description

Part of #6130

Remove .json files that were previously generated by the Go-JSONSchema generation.

These include:

• kube-schema.json
• validation-schema.json
• $$$extension-schema.json

[vaidikcode]

@manusa Could you please assign this issue to me? Also, do I need to delete every file with the names kube, validation, certmanager, and openclustermanager-schema.json? If not, is there a way to identify the files generated by the Go-JSONSchema generation?

[manusa]

This need to wait until all model generation has been refactored to use OpenAPI (currently 5 extensions are yet to be completed).