add final keyword to checkHashes as well

Author: Richard van Heest

src/main/java/gov/loc/repository/bagit/verify/BagVerifier.java

@@ -149,7 +149,7 @@ public final void isValid(final Bag bag, final boolean ignoreHiddenFiles) throws
    * Check the supplied checksum hashes against the generated checksum hashes
    */
   @SuppressWarnings("PMD.AvoidInstantiatingObjectsInLoops")
-  protected void checkHashes(final Manifest manifest) throws CorruptChecksumException, InterruptedException, VerificationException{
+  protected final void checkHashes(final Manifest manifest) throws CorruptChecksumException, InterruptedException, VerificationException{
     final CountDownLatch latch = new CountDownLatch( manifest.getFileToChecksumMap().size());
 
     //TODO maybe return all of these at some point...