chore(types): remove ExecutionPayloadHeader version

[calbera]

A non-critical proposal to clean up tech debt. This PR can be merged now but chosen to be kept as a simple refactor instead of a hard fork by changing this line

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 76.92308% with 12 lines in your changes missing coverage. Please review.

Project coverage is 59.71%. Comparing base (cc7d023) to head (e98b23e).

Files with missing lines	Patch %	Lines
cli/commands/genesis/payload.go	84.37%	2 Missing and 3 partials :warning:
storage/beacondb/eth1.go	62.50%	2 Missing and 1 partial :warning:
cli/commands/genesis/genesis.go	0.00%	1 Missing :warning:
consensus-types/types/payload.go	0.00%	1 Missing :warning:
consensus-types/types/state.go	0.00%	1 Missing :warning:
state-transition/core/state_processor_genesis.go	0.00%	0 Missing and 1 partial :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2701      +/-   ##
==========================================
+ Coverage   59.68%   59.71%   +0.02%     
==========================================
  Files         345      345              
  Lines       15980    15912      -68     
  Branches       22       22              
==========================================
- Hits         9538     9502      -36     
+ Misses       5701     5673      -28     
+ Partials      741      737       -4     

Files with missing lines	Coverage Δ
consensus-types/types/genesis.go	85.89% <100.00%> (-0.18%)	:arrow_down:
consensus-types/types/payload_header.go	95.88% <100.00%> (-0.02%)	:arrow_down:
state-transition/core/state_processor_payload.go	63.86% <100.00%> (ø)
storage/beacondb/kvstore.go	97.54% <100.00%> (-0.03%)	:arrow_down:
storage/encoding/ssz.go	53.84% <ø> (+3.84%)	:arrow_up:
cli/commands/genesis/genesis.go	0.00% <0.00%> (ø)
consensus-types/types/payload.go	92.52% <0.00%> (-0.02%)	:arrow_down:
consensus-types/types/state.go	75.91% <0.00%> (ø)
state-transition/core/state_processor_genesis.go	43.75% <0.00%> (ø)
storage/beacondb/eth1.go	85.00% <62.50%> (+6.42%)	:arrow_up:
... and 1 more

... and 1 file with indirect coverage changes

:rocket: New features to boost your workflow:

• :snowflake: Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[calbera]

Confirming backwards compat with mainnet:

• sync started at height ~860,000
• currently at ~880,000 (so far so good)
• EDIT: good at height ~1mil ✅

[rezbera]

Agree with this change for a later fork. Will review properly after all bectra related work is done