Fix typo

Author: JooHyukKim

protobuf/src/test/java/com/fasterxml/jackson/dataformat/protobuf/testutil/failure/JacksonTestFailureExpected.java

@@ -21,9 +21,7 @@
  *
  *     @Test
  *     @JacksonTestFailureExpected
- *     @Test
-    @Test
-    public void testFeatureNotYetImplemented() {
+ *     public void testFeatureNotYetImplemented() {
  *         // Test code that is expected to fail
  *     }
  * }