Legacy custom roles without a description don't show "No description" in the role dropdown

On the Manage -> Members page for any group/project, clicking on a member's role will show the role details drawer. If the role can be changed, a dropdown will be shown for the role. In the dropdown, custom roles with a description will show the description under the role name. Custom roles without a description do not show any description:

In other places where we show the role name and description, if there is no description, we show No description:

This issue is to discuss whether we want to show No description as well for the dropdown item, or leave it as-is. Note that we now require descriptions for custom roles, so the No description text only applies to "legacy" custom roles that were created before the description was required.