Update mysqlclient requirement from <=2.2,==1.4.6 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](PyMySQL/mysqlclient@v1.4.6...v2.2.4)

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

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

setup.py

@@ -12,7 +12,7 @@
     "pytest-mock>=3.6.1,<=3.11",
     "pytest-django==4.5.2",
     "psycopg2==2.9.5",
-    "mysqlclient==1.4.6,<=2.2",
+    "mysqlclient==2.2.4",
 ]