[PRQ#51673] Deletion Request for python-txsni

MarsSeed [1] filed a deletion request for python-txsni [2]: Abandoned Python module from 2020, with unaddressed use-case breaking issues. [a] Better to delete from AUR, along with its deprecated, defunct consumer, python-txacme (PRQ#48561). [a]: https://github.com/glyph/txsni/issues [1] https://aur.archlinux.org/account/MarsSeed/ [2] https://aur.archlinux.org/pkgbase/python-txsni/