When downoading from sharepoint with buffer size always getting maximum 8K buffer and not as we asked

Describe the bug

When downloading file from sharepoint using graph api and set the buffer size to be downloaded only 8K ( maximum) is fetched ) instread of the given buffer size.
InputStream inputStream = graphServiceClient.drives().byDriveId(driveId).items().byDriveItemId(getDriveItemIdFromRootPath(filePath)).content().get();
byte[] buf = new byte[cloudPartSizeWhenDownloadingToLocal];
int bytesRead;
while ((bytesRead = srcInputStream.read(buf)) != -1) {
byresRead is always maximum 8K and not per demand
}

Expected behavior

The bytess returned from this method should aline with the request.

How to reproduce

see above

SDK Version

6.25.1

Latest version known to work for scenario above?

No response

Known Workarounds

No response

Debug output

</details>


### Configuration

_No response_

### Other information

_No response_

graphServiceClient.drives().byDriveId(...).content().get() 呼び出しから調査を開始し、返された Java InputStream が SharePoint のダウンロードに対する read(byte[]) をどのように処理するかを確認します。観測された 8K の読み取りを Java InputStream の契約および SDK のストリーム実装と比較します。要求されたバッファリング動作が修正されるか、回帰テストで明確にカバーされれば完了です。