Updated meta `license-file` in setup.cfg (#1188)
Updated meta `license-file` in setup.cfg (#1188)

Use underscore in the setup.cfg key to fix the following warning:

> Usage of dash-separated 'license-file' will not be supported in future versions. Please use the underscore name 'license_file' instead
django-crispy-forms/django-crispy-forms,django-crispy-forms/django-crispy-forms