Update httpapi.go

plugin/consensus/raft/httpapi.go

@@ -84,6 +84,8 @@ func serveHTTPRaftAPI(ctx context.Context, port int, confChangeC chan<- raftpb.C
 		srv.Close()
 	case err := <-errorC:
 		srv.Close()
-		rlog.Error(fmt.Sprintf("the errorC chan receive a err (%v)\n", err.Error()))
+		if err != nil {
+		    rlog.Error(fmt.Sprintf("the errorC chan receive a err (%v)\n", err.Error()))
+		}
 	}
 }