Fees going to the gas fee recipient should be based on the actual gas
used (available in the receipt) rather than the gas limit in a
transaction. This fixes Hive test "GetPayloadV2 Block Value".
Also `engine_getPayloadBodiesByRangeV1` params should be encoded as hex
strings.
* Fix a typo
* BlockBuilder dummy
* BlockProposerParametersPOS -> BlockBuilderParameters
* Pass tx to MiningStep
* BlockBuilderFunc
* Interrupt in MiningExec Stage
* Draft implementation of BlockBuilder
* Fail back to empty header
* Add a comment
* cosmetic change
* Cosmetic change again
* It's not safe to pass transactions between goroutines