does not currently work, due to various bugs

Co-Authored-By: Jimmy Jia <tesrin@gmail.com>

This reduces the complexity of the AbstractNav implementation,
especially in regards to how the contexts are integrated with it.

This fixes the assertion issues caused by the selectors testing
implementation details to find the DOM elements, rather than
testing for something that is gauranteed to be in the
implementation (E.g. the class `nav` on the Nav component, since
it's part of the Bootstrap design spec) of the rendered DOM
element.

Currently, we use a ref to gain access to the underlying
component to implement our own functionality. However, this causes
an issue with not allowing the user to forward their own ref
to gain access to the underlying component. using `useMergedRefs`,
we are able to forward both refs to the underlying component.