Convert an organization member to outside collaborator
PUT
/orgs/{org}/outside_collaborators/{username}
When an organization member is converted to an outside collaborator, they'll only have access to the repositories that their current team membership allows. The user will no longer be a member of the organization. For more information, see "Converting an organization member to an outside collaborator". Converting an organization member to an outside collaborator may be restricted by enterprise administrators. For more information, see "Enforcing repository management policies in your enterprise."
🟠403Forbidden if user is the last owner of the organization, not a member of the organization, or if the enterprise enforces a policy for inviting outside collaborators. For more information, see "[Enforcing repository management policies in your enterprise](