www/librewolf: correct the package description

WWW within Makefile is correct.

Remove the WWW line (with a different URL) from pkg-descr.

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=258503#c32

PR:          258503
Reported by: VVD at comment 32
Fixes:       4e77dee7 www/librewolf: New port