feat: add holesky network type

[KolbyML]

What was wrong?

Devnets and testnets are important for ensuring the robustness of Ethereum to continue shipping upgrades. As Portal gets integrated and becomes more important infrastructure for L1's clients, the idea is that Portal would be run by default on testnets, the same way any default feature is run on both main nets and testnets.

How was it fixed?

I am adding a network outline for Holesky as it is the newest testnet, goreli is now discontinued. Future testnets won't have a pre-merge phase. I believe sepolia will be the last testnet (which is still supported) to have any per-merge data.

Anyways there isn't a rush to add sepolia, adding holesky should allow me to fix most of our hardcoded mainnet stuff.

Work left to do in follow-up PR's

• add testing that testnet values work might be an optional flag in hive or some tests in the trin repo, this will be on on-going thing
• Make Trin work with networks other than the mainnet. This will probably result in multiple PRs over time.

In short this is the start