Fix django version check

Author: OskarPersson

sql_server/pyodbc/base.py

@@ -8,7 +8,7 @@
 from django.core.exceptions import ImproperlyConfigured
 from django import VERSION
 
-if VERSION[:3] < (2, 1, 0) or VERSION[:2] >= (2, 2):
+if VERSION[:3] < (2, 2, 0) or VERSION[:2] >= (2, 3):
     raise ImproperlyConfigured("Django %d.%d.%d is not supported." % VERSION[:3])
 
 try: