It should be `givenName` instead of `givenname`. Using the later one, will result in Keycloak bugging out during the sync process, and henceforth displaying an empty user list.
Keycloak seems to default to "First name" being `cn` which LLDAP uses for Display Name, resulting in Users getting duplicated display names in Keycloak (like First Last Last), or missing their first name entirely (when they have no DIsplay Name in LLDAP).
This just updates the example config to provide instructions on changing the attribute mapping in Keycloak to fix this.
