Instant parsing not working correctly on JS

[jakubgwozdz]

Code like "2019-10-28T14:00:00+01:00".toInstant() works ok under JVM, but unfortunately not under JS.
This is caused by js-joda problem where Instant cannot use +01:00 offsets (only Zworks here) and causes

> var Instant = require("@js-joda/core").Instant;
undefined
> Instant.parse('2019-10-28T14:00:00+01:00')
Uncaught:
DateTimeParseException: Text '2019-10-28T14:00:00+01:00' could not be parsed at index 19: 2019-10-28T14:00:00+01:00, at index: 19
    at DateTimeFormatter._parseToBuilder (/Users/jakub.gwozdz/tmp/node_modules/@js-joda/core/dist/js-joda.js:6972:19)
    at DateTimeFormatter.parse2 (/Users/jakub.gwozdz/tmp/node_modules/@js-joda/core/dist/js-joda.js:6933:30)
    at DateTimeFormatter.parse (/Users/jakub.gwozdz/tmp/node_modules/@js-joda/core/dist/js-joda.js:6910:23)
    at Function.parse (/Users/jakub.gwozdz/tmp/node_modules/@js-joda/core/dist/js-joda.js:12368:46) {
  parsedString: [Function],
  errorIndex: [Function],
  toString: [Function]
}

solution would be going through ZonedDateTime:

> ZonedDateTime.parse('2019-10-28T14:00:00+01:00').toInstant()
Instant { _seconds: 1572267600, _nanos: 0 }

[ilya-g]

Relates to #56.
I believe relying on ZonedDateTime.parse can allow more input strings than necessary, though a format can be used to limit allowed formats.

[jakubgwozdz]

Well my use case is in using ktor-client->kotlinx.serialization (in multiplatform, js-browser included). And since the 3rd party rest api endpoint returns datetimes in 2019-10-28T14:00:00+01:00 ISO format, I cannot really use Instant class here.

[ilya-g]

I'm closing this as a duplicate of #56 because essentially it's the same issue.