LibUnicode: Generate a list of available numbering systems

Author: https://github.com/trflynn89
Commit: 481ced53d8
Pull-request: https://github.com/SerenityOS/serenity/pull/12223
Reviewed-by: https://github.com/linusg ✅

Userland/Libraries/LibUnicode/NumberFormat.cpp

@@ -16,6 +16,7 @@
 
 namespace Unicode {
 
+Span<StringView const> __attribute__((weak)) get_available_number_systems() { return {}; }
 Optional<NumberSystem> __attribute__((weak)) number_system_from_string(StringView) { return {}; }
 Optional<StringView> __attribute__((weak)) get_number_system_symbol(StringView, StringView, NumericSymbol) { return {}; }
 Optional<NumberGroupings> __attribute__((weak)) get_number_system_groupings(StringView, StringView) { return {}; }