Format for regional locales is inconsistent

In https://github.com/phetsims/weddell/issues/134, it was reported that the format of the regional locales is inconsistent. It's true - somethings a comma is used and sometimes parentheses are used. Here's a short excerpt of babel\localeData.json that illustrates this:

  "ar_LY": {
    "englishName": "Arabic (Libya)",
    "localizedName": "العربية (ليبيا)",
    "direction": "rtl",
    "fallbackLocales": [
      "ar",
      "ar_MA"
    ]
  },
  "ar_MA": {
    "locale3": "ary",
    "englishName": "Arabic, Morocco",
    "localizedName": "العربية (المغرب)",
    "direction": "rtl",
    "fallbackLocales": [
      "ar"
    ]
  },

I'm not sure how this came about. It may have been like this for years.