Handle possible missing forward slash in url in changeLocale

[RikuVan]

To ensure language changes work when the url does not contain for forward slash, would it be possible to add a check such as this (seems there is a TODO for this):

 if (allSitePage.includes(link) || allSitePage.includes(`${link}/`)) {
    gatsbyNavigate(link)
  } else {
    gatsbyNavigate(`/${language}/`)
  }

If you are just starting out with this this plugin it can be a bit of a head-scratcher at first why language changes do not work as intended.

[wiziple]

allSitePage array is not used anymore since gatsby team fixed matchPath, thanks!