Don't force role of user if no ldap groups defined

We should not force role of user on LDAP logins if there are not Manager/Admin groups defined, return null to get the one from database as before.

app/Core/Ldap/User.php

@@ -121,15 +121,14 @@ class User
      */
     protected function getRole(array $groupIds)
     {
-        $role = Role::APP_USER;
-
         if (! $this->hasGroupsConfigured()) {
-            if (LDAP_USER_DEFAULT_ROLE_MANAGER) {
-                $role = Role::APP_MANAGER;
-            } else {
-                $role = Role::APP_USER;
-            }
-            return $role;
+            return null;
+        }
+	
+        if (LDAP_USER_DEFAULT_ROLE_MANAGER) {
+            $role = Role::APP_MANAGER;
+        } else {
+            $role = Role::APP_USER;
         }
 
         foreach ($groupIds as $groupId) {