Add macOS task to Cirrus CI
Add macOS task to Cirrus CI

Fixes #577.

der-lyse/newsboat,newsboat/newsboat,newsboat/newsboat,der-lyse/newsboat,newsboat/newsboat,der-lyse/newsboat,der-lyse/newsboat,der-lyse/newsboat,der-lyse/newsboat,newsboat/newsboat,newsboat/newsboat,newsboat/newsboat,der-lyse/newsboat,newsboat/newsboat,newsboat/newsboat,der-lyse/newsboat