fix(forks,fw): Fix transition forks on state tests

[marioevz]

🗒️ Description

Fix state test generated using transition forks, so the transition fork is not named in the output fixture, but the actual Fork that should be enabled according to the state test's block number and timestamp.

🔗 Related Issues

Fixes #405

✅ Checklist

• All: Set appropriate labels for the changes.
• All: Considered squashing commits to improve commit history.
• All: Added an entry to CHANGELOG.md.
• All: Considered updating the online docs in the ./docs/ directory.
• Tests: Included the type and version of evm t8n tool used to locally execute test cases: e.g., ref with commit hash or geth 1.13.1-stable-3f40e65.
• Tests: Ran mkdocs serve locally and verified the auto-generated docs for new tests in the Test Case Reference are correctly formatted.

[spencer-tb]

LGTM!