fix(Users): add to, not overwrite, order by clause

Signed-off-by: Arthur Schiwon <blizzz@arthur-schiwon.de>

Author: blizzz

lib/UserBackend.php

@@ -253,7 +253,7 @@ public function getDisplayNames($search = '', $limit = null, $offset = null) {
 			->orWhere($query->expr()->iLike('displayname', $query->createPositionalParameter('%' . $this->db->escapeLikeParameter($search) . '%')))
 			->orWhere($query->expr()->iLike('configvalue', $query->createPositionalParameter('%' . $this->db->escapeLikeParameter($search) . '%')))
 			->orderBy($query->func()->lower('displayname'), 'ASC')
-			->orderBy('uid', 'ASC')
+			->addOrderBy('uid', 'ASC')
 			->setMaxResults($limit)
 			->setFirstResult($offset);