Add Sepolia testnet to chainspec

[lightclient]

This adds the Sepolia testnet as an option for Akula. Genesis information was sourced from here: ethereum/go-ethereum#23730.

[lightclient]

Sync time on my modestly-sized VPS:

start = 2022-05-25T01:17:44.001449Z
end   = 2022-05-25T01:39:23.724067Z

Grabbing the latest block:

$ curl http://localhost:8545 -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getBlockByNumber","params":["latest", false],"id":0}' | jq

{
  "jsonrpc": "2.0",
  "result": {
    "number": "0x11d310",
    "hash": "0x0ea34cc66b2b07f189c44e336ed3a7ec4d51c4d574af8e2b137ab2f715918c94",
    "parentHash": "0xa2b06bf8e25119514deb16e455ac762bc1d83de316770c2786d1e2963415a702",
    "nonce": "0xebe0a3745019e497",
    "sha3Uncles": "0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347",
    "logsBloom": "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
    "transactionsRoot": "0x03a6744937fb33040027bac78d0a48433a4d0ead9a8ea01b237d7ba7cd2b3345",
    "stateRoot": "0xac4e25a64484f6919ec1a956f245de568501f3e86bea2f0d882b6d169b5eb5f4",
    "receiptsRoot": "0x75308898d571eafb5cd8cde8278bf5b3d13c5f6ec074926de3bb895b519264e1",
    "miner": "0x8989859156070a1bc64f8833dbbc19dc1bd1a2b8",
    "difficulty": "0x1a9199907",
    "totalDifficulty": "0xd9c9b15fa875a",
    "sealFields": [
      "0xd897b18889c3e46031cd749a17aec87a912eba191641fe71b3578dec8a6bb2e8",
      "0xebe0a3745019e497"
    ],
    "extraData": "0x796f6c6f73776167",
    "size": "0x0",
    "gasLimit": "0x7a3083",
    "gasUsed": "0xa410",
    "timestamp": "0x628d8ae7",
    "transactions": [
      "0x1835c224007eef24f28b59ac5118d593d14c8d597a1ae37748f725242d2f3eef",
      "0xf393df7d46c8453929c6847cb8411b29055272db9fe54c8019eca196aca0b8dd"
    ],
    "uncles": []
  },
  "id": 0
}

[vorot93]

Thanks!