Use Map#forEach instead of Map#entrySet#forEach

See gh-1449

spring-core/src/main/java/org/springframework/util/LinkedMultiValueMap.java

@@ -195,8 +195,7 @@ public class LinkedMultiValueMap<K, V> implements MultiValueMap<K, V>, Serializa
 	 */
 	public LinkedMultiValueMap<K, V> deepCopy() {
 		LinkedMultiValueMap<K, V> copy = new LinkedMultiValueMap<>(this.targetMap.size());
-		this.targetMap.entrySet().forEach(entry -> 
-			copy.put(entry.getKey(), new LinkedList<>(entry.getValue())));
+		this.targetMap.forEach((k, v) -> copy.put(k, new LinkedList<>(v)));
 		
 		return copy;
 	}