Integrate Dropdown component into the Morpher

Consider integrating the `Dropdown` component into the morpher and maybe rename it to `Select` so that it is more in line with the behaviour provided. The following resources could serve as guidance for how to handle the underlying logic:
- https://react-spectrum.adobe.com/react-aria/useSelect.html
- https://github.com/reach/reach-ui/blob/develop/packages/dropdown/src/index.tsx