Make description of _GROUP_ID more obvious

Author: asmorodskyi

docs/UsersGuide.asciidoc

@@ -1139,7 +1139,7 @@ _INCLUDE_CHILDREN:: Include children that would otherwise not be considered when
 _GROUP:: Job templates *not* matching the given group name are ignored. Does *not*
          affect obsoletion behavior.
 
-_GROUP_ID:: Same as `_GROUP` but allows to specify the group directly by ID.
+_GROUP_ID:: Job templates *not* matching the given group ID are ignored.
 _PRIORITY:: Sets the priority value for the new jobs (which otherwise defaults
 to the priority of the job template)