ObjectProperty(path) {
        if (
          DATA_FETCH_FNS.includes(path.node.value.name) &&
          path.findParent(
            (path) =>
              path.isVariableDeclarator() &&
              path.node.id.name === 'layoutProps',
          )
        ) {
          path.remove()
        }
      }
Currently it's not possible to export data fetching functions from MDX pages
because MDX includes them in `layoutProps`, and Next.js removes them at some
point, causing a `ReferenceError`.

https://github.com/mdx-js/mdx/issues/742#issuecomment-612652071

This plugin can be removed once MDX removes `layoutProps`, at least that
seems to be the current plan.