PROXY: Use right name in ldap filter
We used internal fq name in ldap filter
with id_provider proxy to files and auth provider
ldap
[sssd[be[LDAP]]] [sdap_get_generic_ext_step]
(0x0400): calling ldap_search_ext with
[(&(uid=testuser1@ldap)(objectclass=posixAccount))][dc=example,dc=com].
Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>