Add deneb compatibility to optimistic types

[avalonche]

📝 Summary

The optimistic v2 types were capella specific and did not support Deneb. This PR adds deneb support for the optimistic v2 path.

⛱ Motivation and Context

Enabling optimistic features on the boost-relay as it is a feature implemented by many relays.

📚 References

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✅ I have run these commands

• make lint
• make test-race
• go mod tidy
• I have seen and agree to CONTRIBUTING.md

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 45.33898% with 129 lines in your changes are missing coverage. Please review.

Project coverage is 31.27%. Comparing base (d61f228) to head (4e02e4b).
Report is 9 commits behind head on main.

Files	Patch %	Lines
common/types.go	50.00%	62 Missing and 24 partials ⚠️
common/types_spec.go	0.00%	31 Missing ⚠️
common/utils.go	63.63%	8 Missing and 4 partials ⚠️

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Additional details and impacted files

@@            Coverage Diff             @@
##             main     #615      +/-   ##
==========================================
+ Coverage   30.43%   31.27%   +0.83%     
==========================================
  Files          41       41              
  Lines        6275     6399     +124     
==========================================
+ Hits         1910     2001      +91     
- Misses       4118     4143      +25     
- Partials      247      255       +8     

Flag	Coverage Δ
unittests	31.27% <45.33%> (+0.83%)	⬆️

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