fix(DropdownToggle): add missing proptype (color)

[apaatsio]

No description provided.

[virgofx]

This PR is invalid. It breaks HTML as it leaks the color attribute and is not BS4 compatible. Color needs to be removed.

[apaatsio]

@virgofx Can you elaborate what exactly is breaking? It seems to be working fine for me.

E.g.

<DropdownToggle color="success" caret>Hello</DropdownToggle>

generates

<button type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false" class="dropdown-toggle btn btn-success">Hello</button>

Moreover, if we remove the color property, how are we supposed to change the color of the DropdownToggle?

[virgofx]

Ah, I see this distinction. You were using color for the Button component (which is valid). In my case I was using non-buttons where color is invalid and causes conflicts.

So, I believe the proper solution is to allow color as an optional prop that gets passed into the DropdownToggle dynamic tag child element if and only if the tag is the Button. I can update my PR and add tests if this seems to be correct?

@apaatsio Let me know your thoughts