Minor - fixing SonarQube warning
diff --git a/core/src/main/java/org/apache/sling/cms/core/internal/models/AuthorizableWrapperImpl.java b/core/src/main/java/org/apache/sling/cms/core/internal/models/AuthorizableWrapperImpl.java
index d6d9a90..f4f873b 100644
--- a/core/src/main/java/org/apache/sling/cms/core/internal/models/AuthorizableWrapperImpl.java
+++ b/core/src/main/java/org/apache/sling/cms/core/internal/models/AuthorizableWrapperImpl.java
@@ -86,7 +86,7 @@
 
     @Override
     public Iterator<String> getGroupNames() {
-        Iterable<Group> iterable = () -> getMembership();
+        Iterable<Group> iterable = this::getMembership;
         return StreamSupport.stream(iterable.spliterator(), false).map(g -> {
             try {
                 return g.getPrincipal().getName();