Refactor Soft Delete Specs

Just for more discussion

This one was much harder. There's a few inline comments I want to make for discussion, but I'd also like input on what's left in https://github.com/OregonDigital/oregondigital/blob/feature/TrySoftDeleteSpecs/spec/features/soft_delete_spec.rb , which is primarily "display things that are queried". Any thoughts on how to pull that out? Or is this just the only way to avoid mucking about in Blacklight stuff?
I second @Spaceghost on not testing private methods directly and instead making sure you have a public method that exercises it.