build(deps): update mysqlclient requirement from ~=2.2.0 to ~=2.2.4

build(deps): update mysqlclient requirement from ~=2.2.0 to ~=2.2.4

Updates the requirements on [mysqlclient](https://github.com/PyMySQL/mysqlclient) to permit the latest version.
- [Release notes](https://github.com/PyMySQL/mysqlclient/releases)
- [Changelog](https://github.com/PyMySQL/mysqlclient/blob/main/HISTORY.rst)
- [Commits](https://github.com/PyMySQL/mysqlclient/compare/v2.2.0...v2.2.4)

---
updated-dependencies:
- dependency-name: mysqlclient
  dependency-type: direct:production
...

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