Add generic chain type

[Wodann]

Definition of Done

• Add a struct GenericChainSpec (ideally in a new crate edr_generic)
• Implement the traits outlined in the book for GenericChainSpec such that it can be used from Hardhat
• Treat unknown transaction types as PostEip155Legacy as in the main branch
• Allow remote blocks to have a missing nonce as in main (also see PR with change)
• Reintroduce this test alongside the GenericChainSpec implementation and validate it works (this test cannot work for L1ChainSpec as it would throw an error when detecting unknown transaction types)
• Add test to validate that the generic chain type can parse this eth_getBlockByNumber response (taken from this issue):

  {"jsonrpc":"2.0","result":{"author":"0xa3b079e4b54d2886ccd9cddc1335743bf1b2f0ad","difficulty":"0xfffffffffffffffffffffffffffffffe","extraData":"0x4e65746865726d696e64","gasLimit":"0x663be0","gasUsed":"0x0","hash":"0x12a6d4673bc9a55b5f77d897f32eb0ff15bca32d09d3dff8013e3ff684b0a84d","logsBloom":"0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000","miner":"0xa3b079e4b54d2886ccd9cddc1335743bf1b2f0ad","number":"0x1b000b1","parentHash":"0x26046ba285c7c87ff04783347a5b63cba77d884a11a50a632ea68ba2843b3064","receiptsRoot":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421","sha3Uncles":"0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347","signature":"0x012bb653a98ede38cd88f59fb09c67a8628012e3a4bdd6925a3dee547e0c4f470aa3118d03e4c81b715200aeb34b00f7c67a0a9cd687ff26c2dbc82964d4268a00","size":"0x238","stateRoot":"0x62cb23bc47439bc73eef6bf9fc0e54b1a40ebb3b0cbcfefd6b13cbc79a1095b6","step":343268919,"totalDifficulty":"0x1b000b0ffffffffffffffffffffffffe9dc2118","timestamp":"0x664d5713","transactions":[],"transactionsRoot":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421","uncles":[]},"id":1}

• Replace the registration of the L1 chain type in Hardhat with the Generic chain type.
• Validate that all Hardhat tests pass
• (optional) Incorporate the feature for better error messages when running unknown transaction types by merging main
  • This was listed to keep track, but can be done in a follow-up PR

[Xanewok]

I'll close this as completed by #653 but feel free to re-open it if there's anything else to be done. I assume that the last, optional item on the list will be completed as we merge main into the feature branch in order to prepare it to land in main but I can also look into that if you'd like me to.