tools: Add transactions root calculation

[marioevz]

🗒️ Description

Adds transactions root calculation in blockchain tests, instead of using the one returned by t8n, since it omits the invalid transactions included in the block (which is the correct behavior when producing state tests).

🔗 Related Issues

None

✅ 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 :)