chore(deps): update tokio-util requirement from 0.6 to 0.7 (#695)

Updates the requirements on [tokio-util](https://github.com/tokio-rs/tokio) to permit the latest version.
- [Release notes](https://github.com/tokio-rs/tokio/releases)
- [Commits](https://github.com/tokio-rs/tokio/commits

)

---
updated-dependencies:
- dependency-name: tokio-util
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>