[nis] update mainnet peers file

[gimre-xymcity]

Mainnet peers file still contains Alice2-Alice4 which are non operational anymore.

In general, some better handling of default peers file might be needed...

[0x6861746366574]

How do you propose to handle it, @gimre-xymcity? I'd like to not have another statistics-service, and I believe this should be relying on an archival node anyway, right?

For the interim, we can simply set a fixed node we operate.