@Override protected void processDependencies(List<zipkin2.Span> spans) throws Exception {
      aggregateDependencies(storage, spans);
    }
The current implementation does not include dependency aggregation. It includes retrieval of
pre-aggregated links, usually made via zipkin-dependencies
zipkin-storage/mysql-v1/src/test/java/zipkin2/storage/mysql/v1/ITMySQLStorage.java