Bump @openzeppelin/contracts from 4.4.2 to 4.7.3

Bumps [@openzeppelin/contracts](https://github.com/OpenZeppelin/openzeppelin-contracts) from 4.4.2 to 4.7.3.
- [Release notes](https://github.com/OpenZeppelin/openzeppelin-contracts/releases)
- [Changelog](https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/CHANGELOG.md)
- [Commits](OpenZeppelin/openzeppelin-contracts@v4.4.2...v4.7.3)

---
updated-dependencies:
- dependency-name: "@openzeppelin/contracts"
  dependency-type: direct:production
...

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