build(deps-dev): bump @openzeppelin/contracts-upgradeable

Bumps [@openzeppelin/contracts-upgradeable](https://github.com/OpenZeppelin/openzeppelin-contracts-upgradeable) from 4.6.0 to 4.7.3.
- [Release notes](https://github.com/OpenZeppelin/openzeppelin-contracts-upgradeable/releases)
- [Changelog](https://github.com/OpenZeppelin/openzeppelin-contracts-upgradeable/blob/master/CHANGELOG.md)
- [Commits](OpenZeppelin/openzeppelin-contracts-upgradeable@v4.6.0...v4.7.3)

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

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

package.json

@@ -75,7 +75,7 @@
     "@nomiclabs/hardhat-etherscan": "2.1.7",
     "@nomiclabs/hardhat-web3": "2.0.0",
     "@openzeppelin/contracts": "4.6.0",
-    "@openzeppelin/contracts-upgradeable": "4.6.0",
+    "@openzeppelin/contracts-upgradeable": "4.7.3",
     "@openzeppelin/test-helpers": "0.5.15",
     "@superfluid-finance/ethereum-contracts": "1.2.2",
     "@superfluid-finance/sdk-core": "0.4.2",