Support the new Saudi riyal symbol with formatter API

[0xifarouk]

Is your feature request related to a problem? Please describe.
Formatting currency with code "SAR", doesn't show the new Saudi riyal (⃁) symbol.

Describe the solution you'd like
The API should be updated to support it "⃁", since now it have a unicode "U+20C1".

Additional context
Here is a sample code it explain it more:

let amount = 50
let formatted = amount.formatted(.currency(code: "SAR"))
print(formatted) // SAR 50.00

let saLocale = Locale(identifier: "ar_SA")
let formattedWithSA = amount.formatted(.currency(code: "SAR").locale(saLocale))
print(formattedWithSA) // ‏٥٠٫٠٠ ر.س.‏

[itingliu]

It looks like this data is already incorporated into the current ICU version, so supposedly we can support this. We probably just need to find a way to expose a way to get this variant

[0xifarouk]

@itingliu I think no need to expose as a variant? as it should be the default one.
Previously there was no symbol for Saudi riyal, so the symbol was just a shortcut of the name, but now it's an official symbol like $ for USD.
Saudi riyal symbol - Saudi Central Bank