* Import of Intl.Locale from #39664
* Handle updating es2020.intl and add es2021 for new DateTimeFormatOptions options - re: #39664
* Extends DateTimeFormatOptions for new Intl APIs - re: #45420
* Handle migrating Intl.NumberFormat.formatToParts to es2018 (keeping esnext.intl around)
* Adds Intl.DisplayNames to es2020 - re: #44022
* Remove attributes added in es2021 from es2020 - re: #42944
* Add a reference to es2021 in the command line parser
* Adds some docs about the lib files
* Baselines
* Allow undefined in Intl inputs to allow for ergonomic usage of exactOptionalPropertyTypes - see #45652
* Adds some tests covering the APIs
* Apply suggestions from code review
Co-authored-by: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>
* Handle PR feedback
* More review improvements
Co-authored-by: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>