message: add js doc comment
diff: -
  -
  declare module '@primer/components' {
  type Omit<T, K> = Pick<T, Exclude<keyof T, K>>
  import * as StyledSystem from 'styled-system'
  @@ -324,7 +322,9 @@ declare module '@primer/components' {
  height?: 'sm' | 'md' | 'auto'
  }
  -
  + /**
  + * Overlay is in beta and not intended for public use. Use with caution, API may change.
  + */
  export const Overlay: React.FunctionComponent<OverlayProps>
  export interface PageheadProps extends CommonProps, Omit<React.HTMLAttributes<HTMLDivElement>, 'color'> {}
  @@ -862,7 +862,6 @@ declare module '@primer/components/lib/Overlay' {
  export default Overlay
  }
  -
  declare module '@primer/components/lib/Pagehead' {
  import {Pagehead} from '@primer/components'
  export default Pagehead
  