build(deps-dev): bump @stdlib/string from 0.3.1 to 0.3.3

Bumps [@stdlib/string](https://github.com/stdlib-js/string) from 0.3.1 to 0.3.3.
- [Changelog](https://github.com/stdlib-js/string/blob/main/CHANGELOG.md)
- [Commits](stdlib-js/string@v0.3.1...v0.3.3)

---
updated-dependencies:
- dependency-name: "@stdlib/string"
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>