test Django 4.2 w/ psycopg3

Author: asherf

pyproject.toml

@@ -22,7 +22,7 @@ line-length = 120
 legacy_tox_ini = """
 [tox]
 min_version = 4.4
-envlist = {py37,py38,py39,py310,py311}-django{320}-{end2end,unittests},{py38,py39,py310,py311}-django{400,410,420}-{end2end,unittests},py39-lint
+envlist = {py37,py38,py39,py310,py311}-django{320}-{end2end,unittests},{py38,py39,py310,py311}-django{400,410,420}-{end2end,unittests},{py38,py39,py310,py311}-django{420}-psycopg3,py39-lint
 
 [gh-actions]
 python =
@@ -38,6 +38,8 @@ deps =
     django400: Django>=4.0,<4.1
     django410: Django>=4.1,<4.2
     django420: Django>=4.2,<4.3
+    !psycopg3: psycopg2
+    psycopg3: psycopg3
     coverage
     -rrequirements.txt
 skip_missing_interpreters=true

requirements.txt

@@ -4,7 +4,6 @@ flake8
 prometheus-client>=0.12.0
 pip-prometheus>=1.2.1
 mysqlclient
-psycopg2
 pytest==7.3.1
 pytest-django
 pylibmc