Update example like suggested in the Pull Request

Author: shaardie

example/plugins/microservices/ldap_attribute_store.yaml.example

@@ -85,8 +85,10 @@ config:
       ldap_identifier_attribute: uid
 
       # Override the contructed search_filter with ldap_identifier_attribute
-      # with an own filter. This allows more komplex queries.
+      # with an own filter. This allows more complex queries.
       # {0} will be injected with the ordered_identifier_candidates.
+      # For example:
+      # search_filter: "(&(uid={0})(isMemberOf=authorized))"
       search_filter: None
 
       # Whether to clear values for attributes incoming