B.C. dates convertes year to ****

[loetie]

Dates B.C./A.D. like (eg; {{-2000,1,1},{1,1,1}}) seem to return ****-01-01 as date.
The readme states iso8601 (https://github.com/talentdeficit/jsx) is used.
Iso8601 should support dates B.C./A.D. (https://en.wikipedia.org/wiki/ISO_8601#Years)

I think it happens in this part:
https://github.com/talentdeficit/jsx/blob/main/src/jsx_parser.erl#L125 or 135

Used this to locally test it:

Year = -2000.
Month = 1.
Day = 1.
Hour = 1.
Min = 1.
Sec = 1.
unicode:characters_to_binary(io_lib:format("~4.10.0B-~2.10.0B-~2.10.0BT~2.10.0B:~2.10.0B:~2.10.0BZ",[Year, Month, Day, Hour, Min, Sec]))

Is this a bug? (or am i missing some information about this?)