Doesn't manage the default language at all if it is not ‘en’

[kinooyume]

Hi,

When I set the defaultLanguage to something else than en (I tried with fr and de), I got this behavior:

The Url is redirect to the en url. E.g:

• example.com -> example.com/en
• example.com/mail -> example.com/en/mail

When I try to "force" to the default language, I have a page error:

• example.com/fr -> example.com/en/en/fr -> Not found
• example.com/fr/mail -> example.com/en/en/fr/mail

Here is my gatsby-config.ts:

{
      resolve: `gatsby-plugin-react-i18next`,
      options: {
        localeJsonSourceName: `locale`, // name given to `gatsby-source-filesystem` plugin.
        languages: ['fr', 'en', 'de'],
        defaultLanguage: 'fr',
        fallbackLanguage: 'fr',
        siteUrl: `${siteUrl}`,
        // if you are using trailingSlash gatsby config include it here, as well (the default is 'always')
        trailingSlash: 'always',
        // you can pass any i18next options
        i18nextOptions: {
          interpolation: {
            escapeValue: false, // not needed for react as it escapes by default
          },
          lowerCaseLng: true,
          saveMissing: false,
          keySeparator: false,
          nsSeparator: false,
        },
      },
    }

If I set the defaultLanguage to en, it works as expected.