Remove unneeded type argument

Change-Id: Ia9027f2792d895f4569c0c268f2634ee9130c417
Reviewed-on: https://git.eclipse.org/r/c/platform/eclipse.platform.text/+/180562
Tested-by: Platform Bot <platform-bot@eclipse.org>
Reviewed-by: Alexander Kurtakov <akurtako@redhat.com>

org.eclipse.text.tests/src/org/eclipse/text/tests/Bug401391Test.java

diff --git a/org.eclipse.text.tests/src/org/eclipse/text/tests/Bug401391Test.java b/org.eclipse.text.tests/src/org/eclipse/text/tests/Bug401391Test.java
index 942abb2..9ea4acf 100644
--- a/org.eclipse.text.tests/src/org/eclipse/text/tests/Bug401391Test.java
+++ b/org.eclipse.text.tests/src/org/eclipse/text/tests/Bug401391Test.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2020 Sebastian Zarnekow and others.
+ * Copyright (c) 2020, 2021 Sebastian Zarnekow and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
@@ -83,7 +83,7 @@
 			public Set<Object> keySet() {
 				Set<Object> delegate = original.keySet();
 
-				return new AbstractSet<Object>() {
+				return new AbstractSet<>() {
 
 					@Override
 					public Iterator<Object> iterator() {