Add missing tox envs

tox.ini

@@ -1,9 +1,9 @@
 [tox]
 envlist =
+    py{36}-django{20,22},
+    py{37,36}-django{30,31,32},
+    py{39,38,37}-django{40,41,42},
     py{310,311}-django50,
-    py{39,38,37}-django40,
-    py{37,36}-django30,
-    py{36}-django20,
     py{310,311}-djangomaster
 
 [testenv]
@@ -17,8 +17,11 @@ deps =
     django20: Django>=2.0,<2.1
     django22: Django>=2.2,<2.3
     django30: Django>=3.0,<3.1
+    django31: Django>=3.1,<3.2
     django32: Django>=3.2,<3.3
     django40: Django>=4.0,<4.1
+    django41: Django>=4.1,<4.2
+    django42: Django>=4.2,<4.3
     django50: Django>=5.0,<5.1
     djangomaster: https://github.com/django/django/archive/master.tar.gz
     py{36}-django{20,22}: djangorestframework>=3.11,<3.12