finally bump eslint to 9.x

components/Heading/Heading.tsx

@@ -59,7 +59,7 @@ export type HeadingProps = ComponentPropsWithoutRef<typeof H> & {
 
 const Heading = ({ level, id, divider, children, ...rest }: HeadingProps) => {
   return (
-    <H as={`h${level}`} id={id} divider={divider || level === 2} {...rest}>
+    <H as={`h${level}` as keyof JSX.IntrinsicElements} id={id} divider={divider || level === 2} {...rest}>
       {children}
 
       {/* add anchor link to H2s and H3s. ID is either provided or automatically generated by rehype-slug. */}