Expand the “How to delete a Django application” guide

[Angiep212]

The first step of the "How to delete a Django application" guide instructs users to "Remove all references to the app (imports, foreign keys, etc.)." While this is easily understood by experienced developers, it may not be clear to newer Django users what other references should be checked.

It may be helpful to include a few additional examples to make the documentation more descriptive and reduce the chance of leaving behind references to the removed application.

Some additional examples could include:

• Project settings
• URL references
• Views
• Forms