new(tests): complete header_not_terminated tests

[pdobacz]

🗒️ Description

While investigating tests coverage for evmone I stumbled upon an opportunity to add/complete/migrate some tests for a specific piece of validation logic (the coverage turned out to be there in the end, in ethereum/tests, so the prompt to work on this turned out to be a false trail). Nevertheless, I wanted to contribute this little migration (and some extra tests on the subject). (I ticked it off in the tracker.md)

🔗 Related Issues

na

✅ 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: All converted JSON/YML tests from ethereum/tests have been added to converted-ethereum-tests.txt.
• 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.

[marioevz]

LGTM, thanks!