fix(FloatingMenu): remove wrapper div for portal (#647)
fix(FloatingMenu): remove wrapper div for portal (#647)

Fixes #573.
carbon-design-system/carbon-components,carbon-design-system/carbon-components,carbon-design-system/carbon-components,carbon-design-system/carbon-components-react,joshblack/carbon-components-react,joshblack/carbon-components-react,carbon-design-system/carbon-components-react