Kie Server get Signals API does not resolve MVEL expressions

Issue

The REST API GET

/kie-server/services/rest/server/containers/{containerId}/processes/instances/{pInstanceId}/signals

to retrieve the list of available signal names for process instance pInstanceId does not resolve mvel expressions used on signalRef attribute of catch signal event (i.e. #{signalRefVariable}) but the expression used at design time is returned.