parent property
The resource name of the TagKey's parent.
A TagKey can be parented by an Organization or a Project. For a TagKey
parented by an Organization, its parent must be in the form
organizations/{org_id}. For a TagKey parented by a Project, its parent
can be in the form projects/{project_id} or projects/{project_number}.
Immutable.
Implementation
core.String? parent;