typescript typing: use React.ElementType rather than React.ComponentType

[cheapsteak]

Currently providing overrides using intrinsic elements like

p: {
  component: 'p',
  props: {
    className: 'inline',
  },
},

will result in a typescript error of Type 'string' is not assignable to type 'ComponentType<any>'., even though it works

React.ElementType includes intrinsic elements and I believe is more appropriate here

[quantizor]

LGTM