GitLab-managed apps: use upstream values for rbac.create

What does this MR do?

Use upstream rbac.create value

In any case, Gitlab::Kubernetes::Helm::InstallCommand requires rbac or not to be specified which will set the approriate rbac.create value on installation or upgrade of apps

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation created/updated or follow-up review issue created
• Code review guidelines
• [-] Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content

Performance and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• [-] Tested in all supported browsers