Avoid draining testnet root account funds

[ChaoticTempest]

Ideally, we should not be apart of the problem where testnet funds get drained from the root account. To address this, I recommend doing something like after doing dev-deploy, there's an additional call into scheduling the dev account be deleted after a certain amount of time. This will be hidden underneath the Worker<Testnet> so users don't have to do anything with the time span being configurable. There's already a service out there that allows us to schedule calls in the future called cron.cat, so this would be one of the best uses for that, but open to other solutions here too.

[volovyks]

This approach is good. Let's make sure we have the same logic in NEAR CLI and here, not to confuse the user.

[austinabell]

The issue here is that someone might want to run a workflow on testnet and be able to inspect it far in the future. If it's silently deleted, this might be a bad UX. If someone linked out to an account for reference, it would just show up as not found and it would be very hard to track down what existed before with the current explorer.