Using Role url reversal to support all custom lookup_fields (#86)

[dennisstritzke]

Using the Roles url reversal capabilities to support custom lookup_fields (and other future customisations).
fixes #86

I tried sticking with the current test structure:

• used the request / response testing instead of testing get_success_url directly
• did not test the creation form get as it is unrelated to the issue
• made sure the test actually fails without the changes of this PR
• ... and the collection name has to fit the bookmarks of the tests, right?

To prevent errors of this category, I also checked the code for other locations of manually reversing urls. There aren't any.
(I did that yesterday when I discovered the same problem when subclassing Neapolitan components to properly support nested views. So #86 felt like a call to action. 😅)

[carltongibson]

OK, looks good. Thanks @dennisstritzke 👍

[carltongibson]

https://pypi.org/project/neapolitan/25.1/