text: Title: Tox4: Django test suite database can not be recreated in Tox 4 (works in Tox 3)
  Body: ## Issue
  
  I want to update the test suite of a library from tox 3 to tox 4. I am running tox in parallel mode in Github actions.
  
  Part of the test suite are Django tests that create a test Postgres database (that is supplied by a GitHub actions service docker container).
  
  Somehow in tox 4 the creation of the test database fails. It fails only in Python 3.8 and above (3.7 and below still works)
  
  Here is our working test suite with latest tox 3:
  https://github.com/getsentry/sentry-python/actions/runs/3752739310/jobs/6375243340
  
  And here is the failing tst suite with tox 4.0.16:
  https://github.com/getsentry/sentry-python/actions/runs/3752701362/jobs/6375159457
  
  I only changed the tox version, the rest is the same in the both examples. 
  
  It seems that the Django test suite tries to create the test db although it is already existing (Normally the db is recreated if it is existing)
  
  I have tried to debug this and find out what the originating problem is, but without success. 
  As tox 4 is a complete rewrite it could be anything.
  
  Has anyone any hints what this could be?
  Is the way tox runs parallel tests totally different between tox 3 and 4?
  
  Any help is greatly appreciated!
  