codegen: Conflict with provided Kinds

[bcotton]

I happen to have several Kinds that are generically named, e.g. component, resource, group, system, domain, user.

In a few instances, in generated code, these terms conflict with the generated terms. Here are two such cases:

1. with a kind of resource the package from github.com/grafana/grafana-app-sdk/resource would conflict, and I would have to rename the generated import to sdk_resource
2. with a kind of group the generated constants.go generates a Group const that clashes with the Kind.

#1 is not bad as it manifests in operator code, which is typically on generated once.
#2 is in code that is re-generated often

pkg/generated/resource/group/v1alpha1/constants.go

const (
	// Group is the API group used by all kinds in this package
	Group = "servicemodel.ext.grafana.com"
	// Version is the API version used by all kinds in this package
	Version = "v1alpha1"
)

Perhaps ApiGroup or somesuch