Update pytz requirement from <2020.0,>=2019.1 to >=2019.1,<2024.0

Updates the requirements on [pytz](https://github.com/stub42/pytz) to permit the latest version.
- [Release notes](https://github.com/stub42/pytz/releases)
- [Commits](stub42/pytz@release_2019.1...release_2023.2)

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

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

requirements.txt

@@ -20,7 +20,7 @@ psycopg2-binary>=2.8.5,<3.0
 PyGithub>=1.54.1,<2.0
 pypika>=0.48.1,<1.0
 python-dateutil>=2.8.0,<3.0
-pytz>=2019.1,<2020.0
+pytz>=2019.1,<2024.0
 rest-social-auth>=6.0.0,<7.0
 six>=1.12.0,<2.0
 soupsieve>=1.9,<2.0