Json schema should have a version

[skonto]

The jenerated schema here specifies no version:
"$schema": "http://json-schema.org/schema#".
Libraries for validating json expect a specific version because version 4 is not compatible with version 6.
Check: https://github.com/everit-org/json-schema
That breaks the process of validating a k8s json file.
I had to modify the json schema object to make it work, but I am not sure where the version is documented.

[skonto]

@iocanel thoughts?