message: ssr: Fix Fastboot safelist localhost pseudodomain
  I needed this locally to have the slug-extraction work
  with being served by Fastboot.
diff: @@ -103,7 +103,7 @@ module.exports = function (environment) {
  },
  fastboot: {
  hostWhitelist: hostWhitelistByTarget[process.env.SSR_WEB_ENVIRONMENT] ?? [
  - '/.+.card.space.localhost:\\d+$/',
  + '/.+.card.xyz.localhost:\\d+$/',
  '/^localhost:\\d+$/',
  ],
  },
  