feat: Add support for all rlp.Serializable derived transactions

[mikeshultz]

Right now most of our funcs check for native-types. For example:

ledger-eth-lib/ledgereth/transactions.py

Lines 51 to 60 in 884a25b

	if isinstance(tx, Transaction):
	encoded_tx = encode(tx, Transaction)
	elif isinstance(tx, Type1Transaction):
	encoded_tx = tx.transaction_type.to_byte() + encode(tx, Type1Transaction)
	elif isinstance(tx, Type2Transaction):
	encoded_tx = tx.transaction_type.to_byte() + encode(tx, Type2Transaction)
	else:
	raise ValueError(
	"Only Transaction and Type2Transaction objects are currently supported"
	)

Look into supporting any rlp.Serializable objects to allow for easier integration. May need to validate the objects for the necessary props/types (Python Protocols could be useful?) to make sure but it should be doable.