Adds a member to a group policy. The fields required in the request body depend on the type of security provider the member is in.

• Adding a local user as a member of a group policy requires the following fields: group_policy_id, security_provider_id, and user_id. The field distinguished_name must not be present.
• Adding an LDAP user requires the following fields: group_policy_id and security_provider_id. Either user_id or distinguished_name must be provided but not both.
• Adding an LDAP group requires the following fields: group_policy_id, security_provider_id, and distinguished_name.
• RADIUS, Kerberos, and SAML users require the following fields: group_policy_id, security_provider_id, and user_id. RADIUS users must log into the BeyondTrust product at least once and be provisioned with a user ID.
• Adding a SAML group requires the following fields: group_policy_id, security_provider_id, and group_name. The group_name must be the name of an existing group.