Add engine_getPayloadV2

[pawanjay176]

Issue Addressed

ethereum/execution-apis#314

Proposed Changes

Add an engine_getPayloadV2 method that returns the block value along with the payload. Compare the block value with the bid received from the builder and pick the local execution block if it's of equal or higher value.

Additional Info

This PR assumes that the v2 method is available and queries the endpoint and falls back to the v1 method if the v2 method returns an error. Not certain how we should handle EL's not having the v2 method once it's rolled out in all ELs.
cc @realbigsean @paulhauner

[pawanjay176]

@realbigsean tells me that there was an engine api versioning discussion that happened at devcon where there was a proposal to add a get_methods method to check versions. So we should probably wait for that to get in the specs before working on this.

[michaelsproul]

I'm going to close this in favour of #3934 which is already merged 🎉