fix: upgrade @ethereumjs/util from 8.0.5 to 8.1.0

Snyk has created this PR to upgrade @ethereumjs/util from 8.0.5 to 8.1.0.

See this package in npm:
https://www.npmjs.com/package/@ethereumjs/util

See this project in Snyk:
https://app.snyk.io/org/sammyfilly/project/679beab0-93fb-4ef5-b73f-ab298f92d360?utm_source=github&utm_medium=referral&page=upgrade-pr