django-herald on django 3.2 or above raises ImproperlyConfigured exception

[Apoorva Pandey]

The issue occurs when herald.contrib.auth is added to INSTALLED_APPS. The issue only occurs in django versions 3.2 or above.
Here's the traceback when running the tests:

Traceback (most recent call last):
  File "/Users/apoorva/Desktop/django-herald/runtests.py", line 14, in <module>
    runtests()
  File "/Users/apoorva/Desktop/django-herald/runtests.py", line 10, in runtests
    execute_from_command_line(argv)
  File "/Users/apoorva/Desktop/venvdjango3/lib/python3.9/site-packages/django/core/management/__init__.py", line 419, in execute_from_command_line
    utility.execute()
  File "/Users/apoorva/Desktop/venvdjango3/lib/python3.9/site-packages/django/core/management/__init__.py", line 395, in execute
    django.setup()
  File "/Users/apoorva/Desktop/venvdjango3/lib/python3.9/site-packages/django/__init__.py", line 24, in setup
    apps.populate(settings.INSTALLED_APPS)
  File "/Users/apoorva/Desktop/venvdjango3/lib/python3.9/site-packages/django/apps/registry.py", line 91, in populate
    app_config = AppConfig.create(entry)
  File "/Users/apoorva/Desktop/venvdjango3/lib/python3.9/site-packages/django/apps/config.py", line 255, in create
    return app_config_class(app_name, app_module)
  File "/Users/apoorva/Desktop/venvdjango3/lib/python3.9/site-packages/django/apps/config.py", line 38, in __init__
    raise ImproperlyConfigured(
django.core.exceptions.ImproperlyConfigured: The app label 'herald.contrib.auth' is not a valid Python identifier.

[PJ Farrell]

@apoorvaeternity Fixed in main.