Remove the class `.nav-item` from `.nav-link` inside the non `ul` or `ol` based navs.
This makes the consistency for `.nav-item` (This class will not be required on the `.nav-link`).
`.nav-item` was only required when you use `.nav-fill` or `.nav-justified` on the `.nav`. In other cases, it was redundant. And the purpose of `.nav-item` on `.nav-link`s can be achieved via flexbox utilities as well (Mentioned in the docs also).
