net-p2p/jackett: update to 0.20.643

ChangeLog: https://github.com/Jackett/Jackett/releases

• yggtorrent: make strip season optional.
• kamept: switch to cookie method.
• gktorrent: new domain
• core: add cookie for one request to flaresolverr

PR: 273127
Reported by: tremere@cainites.net (maintainer)