docs: fix markdown lint issues in command docs

cmd/serve/docker/docker.go

@@ -59,7 +59,7 @@ func init() {
 var Command = &cobra.Command{
 	Use:   "docker",
 	Short: `Serve any remote on docker's volume plugin API.`,
-	Long:  help() + vfs.Help(),
+	Long:  help() + strings.TrimSpace(vfs.Help()),
 	Annotations: map[string]string{
 		"versionIntroduced": "v1.56",
 		"groups":            "Filter",

cmd/serve/docker/docker.md

@@ -8,7 +8,8 @@ docker daemon and runs the corresponding code when necessary.
 Docker plugins can run as a managed plugin under control of the docker daemon
 or as an independent native service. For testing, you can just run it directly
 from the command line, for example:
-```
+
+```sh
 sudo rclone serve docker --base-dir /tmp/rclone-volumes --socket-addr localhost:8787 -vv
 ```