[RHV] Adding consumers to the quotas throws "Uncaught exception"

Issue

Adding consumers to the RHV quota throws the Uncaught exception occurred. Please try reloading the page message.
In the /var/log/ovirt-engine/ui.log is possible to see following Exception

ERROR [org.ovirt.engine.ui.frontend.server.gwt.OvirtRemoteLoggingService] (default task-124) [] Uncaught exception: java.lang.ClassCastException
        at java.lang.Throwable.Throwable(Throwable.java:59) [rt.jar:1.8.0_242]
        at java.lang.Exception.Exception(Exception.java:25) [rt.jar:1.8.0_242]
        at java.lang.RuntimeException.RuntimeException(RuntimeException.java:25) [rt.jar:1.8.0_242]
        at java.lang.ClassCastException.ClassCastException(ClassCastException.java:23) [rt.jar:1.8.0_242]
        at javaemul.internal.InternalPreconditions.checkCriticalType(InternalPreconditions.java:139) [gwt-servlet.jar:]
        at com.google.gwt.lang.Cast.castTo(Cast.java:74)
        at org.ovirt.engine.ui.uicommonweb.models.quota.QuotaUserListModel.$lambda$1(QuotaUserListModel.java:237)
        at org.ovirt.engine.ui.uicommonweb.models.quota.QuotaUserListModel$lambda$1$Type.executed(QuotaUserListModel.java:237)