useI18n locale contains `default` when using import

[Sam Blowes]

Importing locale via import causes extra default object in the i18n state

setup

setI18n({
  locale: 'en-en',
  fallback: 'en-en',
  messages: {
    'en-en': enEn,
    'es-es': () => import('@/locales/es-es.json'),
  },
})

en-en

{
  "locale": "en-en",
  "locales": [
    "en-en",
    "es-es"
  ],
  "i18n": {
    "LOGIN": {
      "BUTTONS": {
        "REGISTER": "Register"
      },
    }
  }
}

es-es

{
  "locale": "es-es",
  "locales": [
    "en-en",
    "es-es"
  ],
  "i18n": {
    "LOGIN": {
      "BUTTONS": {
        "REGISTER": "Registrarse"
      },
    },
    "default": {
      "LOGIN": {
        "BUTTONS": {
          "REGISTER": "Registrarse"
        },
      }
    }
  }
}