Rename the api group name to be healthcheck.config.k8s.io

[ziyue-101]

This PR renames the health check api group to be healthcheck.config.k8s.io, which is more OSS compared to the old one.

Fixes #3800

[yuwenma]

I assume config.k8s.io is reserved for core k/k resources. Since the healthcheck is under kpt repo now, maybe you can consider using kpt.dev, like config.healthcheck.kpt.dev? How do you plan to suggest HealthCheck to the kpt users?

CC @droot @mortent @justinsb for inputs

[ziyue-101]

The group is not reserved by kubernetes, at least from this doc. :-) https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.26/#-strong-api-groups-strong-

I am not sure about the convention of Kpt, do all the api group names must contain kpt.dev?
I am happy to change the group name to be more appropriate. waiting for advice;-)

[mortent]

We have used config.k8s.io in the past, but I think we prefer to use something under the kpt.dev domain.

[ziyue-101]

Thanks for the context. Changed to config.healthcheck.kpt.dev.

[yuwenma]

looks good. Thanks for the change.