List MFA key types

<Info icon="fa-light fa-lock" className="permission-callout"> <div className="permission-callout__header"><span className="permission-callout__title"><span className="permission-callout__label">Required permissions</span> <span className="fern-docs-badge small blue subtle rounded-full permission-callout__beta">Beta</span></span> <span className="permission-callout__learn-more">[Learn more](/developers/api-guidelines/permissions#how-permissions-work)</span></div> `User.Mfa.Type` + `List` <div className="permission-callout__roles"><span className="permission-callout__roles-label">Roles:</span> <Badge intent="info">Administrator</Badge> <Badge intent="info">User</Badge> <Badge intent="info">Observer</Badge></div> </Info> Retrieve a list of possible MFA Key types.