Update content/admin/managing-accounts-and-repositories/managing-roles-in-your-enterprise/abilities-of-roles.md

Clarify that user licenses refer to self-service volume licensing

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: Tajaly

content/admin/managing-accounts-and-repositories/managing-roles-in-your-enterprise/abilities-of-roles.md

@@ -68,6 +68,7 @@ Enterprise owners do not have access to organization settings or content by defa
 
 Billing managers only have access to your enterprise's billing settings. They can view and manage:
 
+* {% data variables.product.github %} user licenses for self-serve volume licensing
 * Usage-based billing
 * Other billing settings