devel/zeal: Update to 0.7.0

Remove DEPRECATED/EXPIRATION_DATE. Port now builds against Qt6 and
the WebEngine module.

Pet portlint(1) and portclippy(1).

https://github.com/zealdocs/zeal/releases/tag/v0.7.0

PR: 274750
Reported by: Bartek Jasicki <thindil@laeran.pl.eu.org>
Approved by: rakuco (maintainer)