delete redundent import alias and and type conversion

Signed-off-by: zounengren <zouyee1989@gmail.com>

cmd/containerd/command/main.go

@@ -185,8 +185,8 @@ can be used and modified as necessary as a custom configuration.`
 
 		// run server initialization in a goroutine so we don't end up blocking important things like SIGTERM handling
 		// while the server is initializing.
-		// As an example opening the bolt database will block forever if another containerd is already running and containerd
-		// will have to be be `kill -9`'ed to recover.
+		// As an example, opening the bolt database blocks forever if a containerd instance
+		// is already running, which must then be forcibly terminated (SIGKILL) to recover.
 		chsrv := make(chan srvResp)
 		go func() {
 			defer close(chsrv)