[3.13] gh-124969: Fix locale.nl_langinfo(locale.ALT_DIGITS) (GH-124974) (#125232)

Returns a tuple of up to 100 strings for ALT_DIGITS lookup (an empty tuple on most locales).
Previously it returned the first item of that tuple or an empty string.
(cherry picked from commit 21c04e1a972bd1b6285e0ea41fa107d635bbe43a)