Remove py37 tox environment as we no longer use it

And include py311 and py312 in testenv.

Author: oschwald

setup.cfg

@@ -12,7 +12,7 @@ universal = 1
 disable = duplicate-code
 
 [tox:tox]
-envlist = {py37,py38,py39,py310,py311,py312}-test,py312-{black,lint,flake8,mypy}
+envlist = {py38,py39,py310,py311,py312}-test,py312-{black,lint,flake8,mypy}
 
 [gh-actions]
 python =
@@ -22,7 +22,7 @@ python =
     3.11: py311
     3.12: py312,black,lint,flake8,mypy
 
-[testenv:{py37,py38,py39,py310}-test]
+[testenv:{py38,py39,py310,py311,py312}-test]
 deps =
     mocket
     pytest