JBPM-10193 UI error: unexpected system error occurred when access For…

…m asset and also Task form which have listbox component (#3819) (#3820)

Co-authored-by: Bai Xiaofeng <bxf12315@gmail.com>

kie-wb-common-forms/kie-wb-common-dynamic-forms/kie-wb-common-dynamic-forms-client/src/main/java/org/kie/workbench/common/forms/dynamic/client/rendering/renderers/selectors/SelectorFieldRenderer.java

@@ -66,7 +66,9 @@ public void refreshSelectorOptions() {
                 backendSelectorDataProviderService.call(new RemoteCallback<SelectorData>() {
                     @Override
                     public void callback(SelectorData data) {
-                        refreshSelectorOptions(data);
+                        if (data.getValues() != null) {
+                            refreshSelectorOptions(data);
+                        }
                     }
                 }).getDataFromProvider(renderingContext,
                                        field.getDataProvider());