hardened runtime is prerequisite for notarizing apps, which in turn is
required for new developer IDs with 10.14.5 already and will be required
for all software to run in future versions of macOS

https://developer.apple.com/documentation/security/notarizing_your_app_before_distribution

Change-Id: Ifdf73fb5901be5dd0b62e1a51dee6e57c9816e5f
Reviewed-on: https://gerrit.libreoffice.org/73246
Tested-by: Jenkins
Reviewed-by: Christian Lohmaier <lohmaier+LibreOffice@googlemail.com>