You delete workspaces by selecting their icons in the Workspace Graph pane and then Edit > Delete.
The Delete submenu provides two items for deleting workspaces:
Sources and Codemgr_wsdata Directory. Recursively deletes the contents of the workspace. You are prompted to confirm your decision.
Codemgr_wsdata Directory only. Changes the workspace to a non-workspace directory by deleting only the Codemgr_wsdata subdirectory and removing the icon from the Workspace Graph pane.
In either case Configuring automatically updates records in parent and child workspaces to reflect the deletion of the workspace.