Update DropdownItem to take icon prop #4112
Description
Describe the issue. What is the expected and unexpected behavior?
#4038 updated the DropdownToggle to accept an icon prop to display an icon within the Dropdown which is displayed before any component children (separate from the toggleIndicator icon which appears after the component children).
The DropdownItem should follow this same pattern, rather than wrapping an icon component with a DropdownItemIcon component. See example here.