Limit workspace creation to admins

To help streamline and consolidate workspaces in Hive, we've now limited workspace creation privileges to admins only. For non-admins, the create workspace option will no longer be visible when a user is a member of more than one workspace.

This change will help prevent uncontrolled workspace creation and disorganization across teams.

Thank you to Bri from Elevate Billing, Ursula at Kemper, and Josh at Black & Decker for voting on this feature!