swdb: Disable announcing Gpg4win-4.3.0

* web/swdb.mac: Disable Gpg4win announcment.

Due to an issue in Kleopatra Kleopatra from 4.3.0 queries
for an update for 3.2.0. This causes update checks to always
return that there is an update. Until this is fixed we disable
the update notifications to avoid showing them each time.

• GnuPG-Bug-Id: T6985