XWIKI-21509 Broke Upgrade if Tomcat Service is Running, But Not Enabled

The changes introduced in XWIKI-21509 broke installations where the Tomcat systemd service was not explicitly enabled (for autostart), but started by other means.

As after this change the XWiki postinst scripts only check for systemctl is-enabled, the Tomcat service possibly not restartet although it's running.

Proposal: Check yor both is-enabled AND is-active in the postinst scripts.

(Not sure if it's the cleanest or best approach, but works for me, and appears better to me than just checking for is-enabled.)