Add Alert for Backup and Restore

[WalterWj]

Feature Request

Is your feature request related to a problem? Please describe:

https://docs.pingcap.com/zh/tidb/stable/br-monitoring-and-alert#%E6%97%A5%E5%BF%97%E5%A4%87%E4%BB%BD%E5%91%8A%E8%AD%A6 Well suddenly found that the official website has, but tiup does not have built-in Orz Whether this alarm rule can be built in tiup Describe the feature you'd like:

Why the featue is needed:

Describe alternatives you've considered:

Teachability, Documentation, Adoption, Migration Strategy: