Returns the logout URL for sites that use Wix as their identity provider.
Use this function when your site uses a Wix login page
to handle member authentication. Wix manages the logout flow and redirects the member back to your site afterward.
The returned URL points to the /api/auth/logout route.
The URL to redirect to after logout.
This method doesn't return any custom errors, but may return standard errors. Learn more about standard Wix errors.