Duplicate declaration of indentifying type for repository.

[junghoon-vans]

Duplicate indentifyingType declaration in ElasticsearchRepositoryConfigExtension.java.
It looks like we can remove one from that syntax.

@Override
protected Collection<Class<?>> getIdentifyingTypes() {
  return Arrays.asList(ElasticsearchRepository.class, ElasticsearchRepository.class); // Remove one or the other
}