[RFC-191]: EVM-759 - Don't use hardcoded addresses for governance contracts

[goran-ethernal]

Description

This PR introduces new fields to governanceConfig part of genesis.json:

• childGovernorAddr - address of ChildGovernor contract on supernet.
• childTimelockAddr - address of ChildTimelock contract on supernet.
• networkParamsAddr - address of NetworkParams contract on supernet.
• forkParamsAddr - address of ForkParams contract on supernet.

We need to add them to genesis.json because, on live chains, these contracts will be deployed on random addresses, so the user needs to manually change the genesis.json file to keep those addresses as well, so that edge client knows how to handle governance events.

If the chain is started a new on the release that introduces governance, these fields will be automatically updated in genesis.json since on genesis we deploy these contracts automatically on predefined addresses.

Changes include

• Bugfix (non-breaking change that solves an issue)
• Hotfix (change that solves an urgent issue, and requires immediate attention)
• New feature (non-breaking change that adds functionality)
• Breaking change (change that is not backwards-compatible and/or changes current functionality)

Checklist

• I have assigned this PR to myself
• I have added at least 1 reviewer
• I have added the relevant labels
• I have updated the official documentation
• I have added sufficient documentation in code

Testing

• I have tested this code with the official test suite
• I have tested this code manually