Restrict Django dependency to currently supported version

Maybe this will stop complaints about errors with Django
versions that we don't support yet.

Author: Photonios

setup.py

@@ -63,7 +63,7 @@ def run(self):
     ],
     python_requires=">=3.6",
     install_requires=[
-        "Django>=2.0",
+        "Django>=2.0,<5.0",
         "python-dateutil>=2.8.0,<=3.0.0",
         "ansimarkup>=1.4.0,<=2.0.0",
     ],