refactor: Change parameters format in genesis.json

[dima74]

Context

Fixes #4813

Solution

Changes format of genesis.json from (full format):

{
  ...
  "parameters": [
    {
      "Sumeragi": {
        "BlockTimeMs": 2000
      }
    },
    {
      "Sumeragi": {
        "CommitTimeMs": 4000
      }
    },
    ...
    {
      "Transaction": {
        "MaxInstructions": 4096
      }
    },
    ...

to (full format):

{
  ...
  "parameters": {
    "sumeragi": {
      "block_time_ms": 2000,
      "commit_time_ms": 4000,
      ...
    },
    "transaction": {
      "max_instructions": 4096,
      ...
    },
    ...

Migration Guide (optional)

• kagami genesis generate will generate genesis in the new format. Custom genesis generator tools should be changed to new format.
• Note that schema.json has type entry RawGenesisTransaction corresponding to genesis.json file

Review notes (optional)

Checklist

• I've read CONTRIBUTING.md.
• (optional) I've written unit tests for the code changes.
• All review comments have been resolved.

[github-actions]

@BAStos525

[Erigara]

No objections from codewise perspective and imo genesis this way looks more readable.

Let's see what SDK guys think: @Mingela @SamHSmith @0x009922

[dima74]

@BAStos525 @timofeevmd format of parameters in genesis.json has changed. Please see PR description for details of the new format.