upgrade tor package to v0.4.6.9-r0 (see below)
https://web.archive.org/web/20211228082801/https://gitweb.torproject.org/tor.git/plain/ChangeLog
https://git.alpinelinux.org/aports/commit/community/tor?h=3.15-stable&id=cacb3a44facfe85ca04ca1868ecf0f0fbaeae190
https://github.com/fphammerle/docker-tor-obfs4-bridge/commit/127af8a9b1235120bba8dc40b609dc3bf20b4566