message: Fix matomo generation to only happen in production
diff: export default ({ router }) => {
  // Google analytics integration
  - if (MATOMO_SITE_ID && MATOMO_TRACKER_URL) {
  + if (process.env.NODE_ENV === 'production' && typeof window !== 'undefined' && MATOMO_SITE_ID && MATOMO_TRACKER_URL) {
  var _paq = _paq || [];
  /* tracker methods like "setCustomDimension" should be called before "trackPageView" */
  _paq.push(['trackPageView']);
  