Update built-in network alias configuration

Status: draft until we know for sure that Giganode should be removed from bootstrap peers. They will possibly be replaced by other IPs (@Ochem may update this MR directly with those new IPs).

Context

• Ghostnet had a user-activated upgrade.
• Giganode announced shutting down their bootstrap peers.
• Hangzhounet and Jakartanet are deprecated now that Kathmandu is live on Mainnet.

Manually testing the MR

Use ./tezos-node config init --network to start nodes on the various networks that you expect to still exist and check that it bootstraps a bit.

Checklist

• For new features and bug fixes, add an item in the appropriate changelog (docs/protocols/alpha.rst for the protocol and the environment, CHANGES.rst at the root of the repository for everything else).
• Select suitable reviewers using the Reviewers field below.
• Select as Assignee the next person who should take action on that MR