Add support for flashblocks number contract builder tx

[avalonche]

📝 Summary

Integrates with the flashblocks number contract

💡 Motivation and Context

Allow contracts onchain to fill orders based on the flashblock number. Also improves observability of when each Flashblock starts.

---

✅ I have completed the following steps:

• Run make lint
• Run make test
• Added tests (if applicable)

[noot]

Suggested change

	if let Some(flashblocks_number_contract_address) =
	self.0.specific.flashblocks_number_contract_address
	{
	self.spawn_payload_builder_service(
	ctx,
	pool,
	FlashblocksNumberBuilderTx::new(
	signer,
	flashblocks_number_contract_address,
	flashtestations_builder_tx,
	),
	)
	} else {
	self.spawn_payload_builder_service(
	ctx,
	pool,
	FlashblocksBuilderTx::new(signer, flashtestations_builder_tx),
	)
	}
	let builder_tx = if let Some(flashblocks_number_contract_address) = self.0.specific.flashblocks_number_contract_address {
	FlashblocksNumberBuilderTx::new(
	signer,
	flashblocks_number_contract_address,
	flashtestations_builder_tx,
	)
	} else {
	FlashblocksBuilderTx::new(signer, flashtestations_builder_tx)
	};
	self.spawn_payload_builder_service(
	ctx,
	pool,
	builder_tx,
	)

[avalonche]

does this work? I think it'll cause complier errors

[noot]

ah no due to the use of generics. like i mentioned on the other PR would be good to refactor this into an enum