Updated tox after Django 5.2a1. (#2127)

Author: carltongibson

tox.ini

@@ -3,7 +3,8 @@ envlist =
     py{38,39,310,311}-dj42
     py{310,311,312}-dj50
     py{310,311,312,313}-dj51
-    py{310,311,312,313}-djmain
+    py{310,311,312,313}-dj52
+    py{312,313}-djmain
     qa
 
 [testenv]
@@ -13,7 +14,8 @@ commands =
 deps =
     dj42: Django>=4.2,<5.0
     dj50: Django>=5.0,<5.1
-    dj51: Django>=5.1a1,<5.2
+    dj51: Django>=5.1,<5.2
+    dj52: Django>=5.2a1,<6.0
     djmain: https://github.com/django/django/archive/main.tar.gz
 
 [testenv:qa]