LibUnicode: Parse number system digits from the CLDR

We had a hard-coded table of number system digits copied from ECMA-402.
Turns out these digits are in the CLDR, so let's parse the digits from
there instead of hard-coding them.

Userland/Libraries/LibUnicode/Forward.h

@@ -28,6 +28,7 @@ enum class ListPatternStyle : u8;
 enum class ListPatternType : u8;
 enum class Locale : u16;
 enum class Month : u8;
+enum class NumberSystem : u8;
 enum class NumericSymbol : u8;
 enum class Property : u8;
 enum class Script : u8;