Param value for --wait-timeout can not be negative number

[seiya-annie]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. What did you do?
   input tiup dm display test1 --wait-timeout -1

2. What did you expect to see?

return error for param invalid

3. What did you see instead?

[root@localhost ~]# tiup dm display test1 --wait-timeout -1
Starting component dm: /root/.tiup/components/dm/v1.1.2/tiup-dm display test1 --wait-timeout -1
dm Cluster: test1
dm Version: v2.0.0-rc
ID Role Host Ports OS/Arch Status Data Dir Deploy Dir

---

172.16.5.197:9093 alertmanager 172.16.5.197 9093/9094 linux/x86_64 Up /home/tidb/dm/data/alertmanager-9093 /home/tidb/dm/deploy/alertmanager-9093
172.16.5.197:8261 dm-master 172.16.5.197 8261/8291 linux/x86_64 Healthy|L /home/tidb/dm/data/dm-master-8261 /home/tidb/dm/deploy/dm-master-8261
172.16.5.197:8262 dm-worker 172.16.5.197 8262 linux/x86_64 Free /home/tidb/dm/data/dm-worker-8262 /home/tidb/dm/deploy/dm-worker-8262
172.16.5.197:3000 grafana 172.16.5.197 3000 linux/x86_64 Up - /home/tidb/dm/deploy/grafana-3000
172.16.5.197:9090 prometheus 172.16.5.197 9090 linux/x86_64 Up /home/tidb/dm/data/prometheus-9090 /home/tidb/dm/deploy/prometheus-9090
[root@localhost ~]#

4. What version of TiUP are you using (tiup --version)?
   [root@localhost ~]# tiup --version
   v1.0.9 tiup
   Go Version: go1.13
   Git Branch: master
   GitHash: 41fbacf
   [root@localhost ~]# tiup dm --version
   Starting component dm: /root/.tiup/components/dm/v1.1.2/tiup-dm --version
   tiup version v1.1.2 tiup
   Go Version: go1.13
   Git Branch: release-1.1
   GitHash: 7cb85b9-dirty
   [root@localhost ~]#