If a sock puppet votes on a question or an answer, how many times can it do that before the account gets suspended or deleted?
TL;DR: it's not relevant. One vote is enough.
I don't think it's related to the amount. Also, the sock account is deleted or merged with the main account, and the suspension is applied to the main account, otherwise it's pointless.
Once a moderator finds out about a sock abusing votes, the action would be instant, whether it was one vote or 1000 votes.
The amount does have effect on the suspension length though, e.g. one "bad" vote might lead to only one day suspension as warning, while 1000 bad votes can easily give a full year suspension to the main account.