OPENSUSE-SU-2026:21153-1 Security update for xar

This update for xar fixes the following issues: Changes in xar: - Switch to the maintained Apple xar lineage build 503, versioned 1.8.0.0.503: the mackyle 1.6.1 fork this package tracked has been dead since 2012, and Debian, Fedora and Gentoo all moved to Apple's xar apple-oss-distributions/xar...