build(deps): bump serial_test from 3.3.1 to 3.4.0 in the crates-io group

Bumps the crates-io group with 1 update: [serial_test](https://github.com/palfrey/serial_test).


Updates `serial_test` from 3.3.1 to 3.4.0
- [Release notes](https://github.com/palfrey/serial_test/releases)
- [Commits](palfrey/serial_test@v3.3.1...v3.4.0)

---
updated-dependencies:
- dependency-name: serial_test
  dependency-version: 3.4.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: crates-io
...

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Author: dependabot[bot]