message: Define 'SelectMenuItemProps' as a [discriminated union](https://www.typescriptlang.org/docs/handbook/advanced-types.html#discriminated-unions)
diff: @@ -302,10 +302,16 @@ declare module '@primer/components' {
  export interface SelectMenuListProps extends CommonProps, Omit<React.HTMLAttributes<HTMLDivElement>, 'color'> {}
  - export interface SelectMenuItemProps extends CommonProps,
  - Omit<React.AnchorHTMLAttributes<HTMLAnchorElement>, 'color'> {
  - selected?: boolean
  + interface SelectMenuItemCommonProps extends CommonProps {
  + selected?: boolean;
  + }
  + interface SelectMenuItemAsButtonProps extends SelectMenuItemCommonProps, Omit<React.ButtonHTMLAttributes<HTMLButtonElement>, 'color'> {
  + as: "button"
  + }
  + interface SelectMenuItemAsAnchorProps extends SelectMenuItemCommonProps, Omit<React.AnchorHTMLAttributes<HTMLAnchorElement>, 'color'> {
  + as: "a"
  }
  + export type SelectMenuItemProps = SelectMenuItemAsButtonProps | SelectMenuItemAsAnchorProps;
  export interface SelectMenuFooterProps extends CommonProps, Omit<React.HTMLAttributes<HTMLElement>, 'color'> {}
  