[3.13] gh-53203: Fix strptime() for %c, %x and %X formats on some locales (GH-135971)

[miss-islington]

• Add detection of decimal non-ASCII alt digits.
• Add support of non-decimal alt digits on locale lzh_TW.
• Accept only numbers in correct range if alt digits are known.
• Fix bug in detecting the position of the week day name on locales byn_ER and wal_ET.
• Fix support of single-digit hour on locales ar_SA and bg_BG.
• Add support for %T, %R, %r, %C, %OC.
• Prepare code to use nl_langinfo().
  (cherry picked from commit 07183eb)

Co-authored-by: Serhiy Storchaka [email protected]

• Issue: strptime(.., '%c') fails to parse output of strftime('%c', ..) in some locales #53203