Network auto-retry when met errors on accessing tiup backend

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Feature Request

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

I met an error when running tiup, this seem like network issues:

Describe the feature you'd like:

Auto retry when met errors on accessing tiup backend.

Why the featue is needed:

Network errors are not rare issues, it would be much friendly if tiup can auto retry to access its backend.

Describe alternatives you've considered:

Teachability, Documentation, Adoption, Migration Strategy: