An external identity provisioned by SAML SSO or SCIM. If SAML is configured on
the organization, the external identity is visible to (1) organization owners,
(2) organization owners' personal access tokens (classic) with read:org or
admin:org scope, (3) GitHub App with an installation token with read or write
access to members. If SAML is configured on the enterprise, the external
identity is visible to (1) enterprise owners, (2) enterprise owners' personal
access tokens (classic) with read:enterprise or admin:enterprise scope.