@Test
  public void stitchedUploadTest() throws Exception {
    Account account = ACCOUNT_SERVICE.createAndAddRandomAccount();
    Container container = account.getContainerById(Container.DEFAULT_PRIVATE_CONTAINER_ID);
    Pair<List<String>, byte[]> idsAndContent = uploadDataChunksAndVerify(account, container, null, 50, 50, 50, 50, 17);
    stitchBlobAndVerify(account, container, idsAndContent.getFirst(), idsAndContent.getSecond(), 217);
    idsAndContent = uploadDataChunksAndVerify(account, container, FRONTEND_CONFIG.chunkUploadMaxChunkTtlSecs, 167);
    stitchBlobAndVerify(account, container, idsAndContent.getFirst(), idsAndContent.getSecond(), 167);
  }
Test the stitched (multipart) upload flow. This includes generating signed chunk upload URLs, uploading chunks to
that URL, calling the /stitch API to create a stitched blob, and performing get/head/ttlUpdate/delete operations on
the stitched blob.
@throws Exception
ambry-frontend/src/integration-test/java/com/github/ambry/frontend/FrontendIntegrationTest.java