Values.InvitationSourceContains information about the invitation to become a member account.
type nonrec t = {accountId : AccountId.t option;The ID of the account that the invitation was sent from.
*)invitationId : String_.t option;The ID of the invitation. This value is used to validate the inviter account to the member account.
*)relationshipStatus : String_.t option;The status of the relationship between the inviter and invitee accounts.
*)invitedAt : String_.t option;The timestamp when the invitation was sent.
*)}