S3Client.completeMultipartUpload uploads a multipart object to an S3 bucket.
|bucketName||string||Name of the bucket to delete the object to.|
|objectKey||string||Name of the uploaded object.|
|uploadId||number||UploadId of the multipart upload to complete.|
|parts||Array<S3Part>||The S3Parts to assemble.|
|Promise<void>||A Promise that fulfills when the multipart upload has been completed.|