feat: show a message if user attempts to use pro / platform features

[lizardruss]

What issue type does this pull request address?
/kind enhancement

What does this pull request do? Which issues does it resolve?
resolves ENG-3327

Please provide a short message that should be published in the vcluster release notes
Log a message if user attempt to use a pro feature before supported

What else do we need to know?
Currently logs a message any time any pro feature is enabled, but an additional way to disable the check may be desired.

Also adds missing pro attributes for schema partials generation.

[netlify]

✅ Deploy Preview for vcluster-docs canceled.

Name	Link
🔨 Latest commit	75e98ff
🔍 Latest deploy log	https://app.netlify.com/sites/vcluster-docs/deploys/661cedfef0560c00081eb2ea

[heiko-braun]

Fabians latest changes in essence add an ENV VAR that allow to override the checks Russ has put into place:

func ShouldCheckForProFeatures() bool {
	return os.Getenv("FORCE_VCLUSTER_PRO") != "true"
}