Bump @openzeppelin/contracts from 4.8.1 to 4.9.3

Bumps [@openzeppelin/contracts](https://github.com/OpenZeppelin/openzeppelin-contracts) from 4.8.1 to 4.9.3.
- [Release notes](https://github.com/OpenZeppelin/openzeppelin-contracts/releases)
- [Changelog](https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v4.9.3/CHANGELOG.md)
- [Commits](OpenZeppelin/openzeppelin-contracts@v4.8.1...v4.9.3)

---
updated-dependencies:
- dependency-name: "@openzeppelin/contracts"
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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