update option for docker commands

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

docs/reference/commandline/exec.md

@@ -15,6 +15,7 @@ Usage:  docker exec [OPTIONS] CONTAINER COMMAND [ARG...]
 
 Run a command in a running container
 
+Options:
   -d, --detach         Detached mode: run command in the background
       --detach-keys    Override the key sequence for detaching a container
       --help           Print usage

docs/reference/commandline/inspect.md

@@ -16,6 +16,7 @@ Usage:  docker inspect [OPTIONS] NAME|ID [NAME|ID...]
 Return low-level information on one or multiple containers, images, volumes,
 networks, nodes, services, or tasks identified by name or ID.
 
+Options:
   -f, --format       Format the output using the given go template
       --help         Print usage
   -s, --size         Display total file sizes if the type is container