Fix UnusedPrivateField

Signed-off-by: Piotrek Zygielo <piotr@zygielo.pl>
diff --git a/impl/src/main/java/com/sun/el/stream/Optional.java b/impl/src/main/java/com/sun/el/stream/Optional.java
index 6f529d4..b3b13eb 100644
--- a/impl/src/main/java/com/sun/el/stream/Optional.java
+++ b/impl/src/main/java/com/sun/el/stream/Optional.java
@@ -20,7 +20,6 @@
 
 public class Optional {
 
-    private final static Optional EMPTY = new Optional();
     private final Object value;
 
     Optional(Object value) {