nested-structs: show issue with "struct{}" detection

[sbunce]

Background

This pull request is to demonstrate issue in https://github.com/mgechev/revive/issues/824

It seems like the intent is to not fail on "struct{}".

[sbunce]

The syntax is go generics.

I put it on go playground here. https://go.dev/play/p/XSgqTLsjaS_N

I think the 1.17 test is failing because generics was introduced in go1.18.

[chavacava]

Closing this PR. The example is already mentioned in #824 Thanks!