converters/py-unidecode: update to 1.3.7

Changelog: https://github.com/avian2/unidecode/blob/unidecode-1.3.7/ChangeLog

PR: 275283
MFH: 2024Q1
Approved by: douglas@douglasthrift.net (maintainer timeout)

(cherry picked from commit 1b4e67f3e0f60b253537985fb838085e91434b35)