avoid NPE

Author: SamuelGaro

core/provisioning-java/src/main/java/org/apache/syncope/core/provisioning/java/pushpull/AbstractPushResultHandler.java

@@ -215,9 +215,9 @@ protected void assign(final Any<?> any, final Boolean enabled, final Provisionin
     }
 
     protected void copyDynMembershipConds(final Any<?> any, final AnyUR req) {
-        if (any instanceof Group
-                && (((Group) any).getUDynMembership() != null || !((Group) any).getADynMemberships().isEmpty())) {
-            ((GroupUR) req).setUDynMembershipCond(((Group) any).getUDynMembership().getFIQLCond());
+        if (any instanceof Group) {
+            Optional.ofNullable(((Group) any).getUDynMembership()).
+            ifPresent(udc ->  ((GroupUR) req).setUDynMembershipCond(udc.getFIQLCond()));
 
             ((Group) any).getADynMemberships().forEach(aDynGroupMembership ->
                     ((GroupUR) req).getADynMembershipConds().put(