* use EF consensus spec v1.5.0-alpha.6 test vectors
* LC changes are good as is, no need for the debug comment
* Fix indentation
* Use `execution_requests` for requests root
* fill in spec reference URLs for ExecutionPayload(Header)
* copy `execution_requests` when blidning blocks for Electra and add test
* fix `test_engine_api_conversions`
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Co-authored-by: Etan Kissling <etan@nimbus.team>
Jacek Sieka
tersec
Agnish Ghosh