Use ListUtils.filter instead of map for filtering empty elements

Author: Jenson3210

rewrite-java/src/main/java/org/openrewrite/java/AddOrUpdateAnnotationAttribute.java

@@ -400,7 +400,7 @@ private List<Expression> updateInitializer(J.Annotation annotation, List<Express
                 newItemsList.add(new J.Literal(randomId(), SINGLE_SPACE, EMPTY, attribute, maybeQuoteStringArgument(annotation, attribute), null, JavaType.Primitive.String));
             }
             // Filter out empty elements (e.g., from an empty array initializer `{}`)
-            List<Expression> nonEmptyInitializer = ListUtils.map(initializerList, it -> it instanceof J.Empty ? null : it);
+            List<Expression> nonEmptyInitializer = ListUtils.filter(initializerList, it -> !(it instanceof J.Empty));
             return ListUtils.concatAll(nonEmptyInitializer, newItemsList);
         }