Fix another buffer leak in XmlFrameDecoderTest

codec/src/test/java/io/netty/handler/codec/xml/XmlFrameDecoderTest.java

@@ -162,9 +162,13 @@ public class XmlFrameDecoderTest {
             actual.add(cause.getClass());
         }
 
+        try {
             List<Object> expectedList = new ArrayList<Object>();
             Collections.addAll(expectedList, expected);
             assertThat(actual, is(expectedList));
+        } finally {
+            ch.finish();
+        }
     }
 
     private String sample(String number) throws IOException, URISyntaxException {