Fix inconsisticy for service logs

Signed-off-by: yuexiao-wang <wang.yuexiao@zte.com.cn>

docs/reference/commandline/index.md

@@ -143,7 +143,7 @@ read the [`dockerd`](dockerd.md) reference page.
 |:--------|:-------------------------------------------------------------------|
 | [service create](service_create.md) | Create a new service                   |
 | [service inspect](service_inspect.md) | Inspect a service                    |
-| [service logs](service_logs.md)  | Fetch the logs of a service               |
+| [service logs](service_logs.md)  | Fetch the logs of a service or task       |
 | [service ls](service_ls.md) | List services in the swarm                     |
 | [service ps](service_ps.md) | List the tasks of a service              |
 | [service rm](service_rm.md) | Remove a service from the swarm                |

docs/reference/commandline/service.md

@@ -26,7 +26,7 @@ Options:
 Commands:
   create      Create a new service
   inspect     Display detailed information on one or more services
-  logs        Fetch the logs of a service
+  logs        Fetch the logs of a service or task
   ls          List services
   ps          List the tasks of one or more services
   rm          Remove one or more services