Implement ref forwarding on Icon components

[laurenraddatz]

🚀 Feature Proposal

I am requesting to add an iconRef prop on the icon components, and forwarding it to the ref prop on the icon components.

Motivation

this is already enabled in the button components, such as IconButton. In our use case, we have refs with interesting types, such as ones that are callbacks.

Example

reference the IconButton component.

let me know what you think and I can make a PR!

[mannycarrera4]

I think we want to do this for most of our components! For reference: #548