test more ways of calling formatInTimeZone()

[patrik-csak]

No description provided.

[marnusw]

I see the issue now. This breaks when passing the offset to Intl.DTF which expects an IANA time zone name: In src/_lib/tzIntlTimeZoneName/index.js#30

return new Intl.DateTimeFormat(locale ? [locale.code, 'en-US'] : undefined, {
    timeZone: timeZone,
    timeZoneName: length,
  })

I'll have to think about it, but I don't see how one could get the tz name from an offset. Furthermore, one couldn't really say what the expected name would be when there are multiple time zone names per offset. That may well be why DTF doesn't support it. I will change the documentation to reflect this.