Output action items for users when some dependency issues are found about deptry

[fpgmaas]

Thanks for raising the issue @lisphilar! I can see how finding the solution once deptry raises an error can be difficult. However, I wonder if showing potential solutions in the command line is a good idea. Depending on the situation the solution might be different, and users might implement the wrong solution for their problem. Another reason why I think it might not be a good idea, is that the terminal output would become a bit long.

Alternatively, I see that in the documentation, the following is stated regarding DEP002:

deptry will report requests as an unused dependency because it is not used in the project.
To fix the issue, requests should be removed from [project.dependencies].

And

This check can be disabled with Skip unused option.
Specific dependencies can be ignored with Ignore unused option.

I would feel more for elaborating in the documentation, e.g. by adding more examples for each type of issue and/or by making sure the right information is easier for users to find in the documentation.