[Repository] Add core and plugin integration tests for multi stream download APIs

[kotwanikunal]

Is your feature request related to a problem? Please describe.

• Multi-stream download support was added as a part of Add async blob read and download support using multiple streams #9592 using two new APIs readBlobAsync(String blobName, ActionListener<ReadContext> listener) and asyncBlobDownload(String blobName, Path fileLocation, ThreadPool threadPool, ActionListener<String> completionListener)
• Integration tests are added as a part of

  OpenSearch/server/src/internalClusterTest/java/org/opensearch/remotestore/multipart/RemoteStoreMultipartIT.java

  Line 38 in b5cc002

  public class RemoteStoreMultipartIT extends RemoteStoreIT {

• This task will focus on adding any additional integration tests for plugins (S3) and core to test the APIs

Describe the solution you'd like

• Add additional integration tests covering core and plugins for async multi stream segment downloads

Describe alternatives you've considered

• N/A

Additional context

• [Repository] Support multi-stream downloads within Repository #8596