Polish more AssertJ assertions

samples/xml/gae/src/test/java/samples/gae/security/AppRoleTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -37,7 +37,7 @@ public class AppRoleTests {
 	public void bitsAreCorrect() throws Exception {
 		// If this fails, someone has modified the Enum and the Datastore is probably
 		// corrupt!
-		assertThat(ADMIN.getBit()).isEqualTo(0);
+		assertThat(ADMIN.getBit()).isZero();
 		assertThat(NEW_USER.getBit()).isEqualTo(1);
 		assertThat(USER.getBit()).isEqualTo(2);
 	}