Add assertNotInHTML to pytest_django.asserts

[tobami]

While assertInHTML can be imported from pytest_django.asserts, the newer (since 5.1) assertNotInHTML is not available.

[kingbuzzman]

By "is not available" you mean, the autocomplete? And the linter is throwing errors? Because the code uses the current version's TestCase you have installed of Django and if it's there you will be able to use it.

Can you make a PR for this please? The code is here.

[tobami]

You are right, it is available as an import, it's the IDE (VSCode) that doesn't recognise it as a valid import when syntax highlighting (which is a bit more important than autocomplete working).

PR created! #1200