allow sha256 payload to be configurable for object perf test (#18712)

Signed-off-by: Zhou Ting <ting.z.zhou@intel.com>

cmd/peer-rest-client.go

@@ -921,6 +921,7 @@ func (client *peerRESTClient) SpeedTest(ctx context.Context, opts speedTestOpts)
 	values.Set(peerRESTDuration, opts.duration.String())
 	values.Set(peerRESTStorageClass, opts.storageClass)
 	values.Set(peerRESTBucket, opts.bucketName)
+	values.Set(peerRESTEnableSha256, strconv.FormatBool(opts.enableSha256))
 
 	respBody, err := client.callWithContext(context.Background(), peerRESTMethodSpeedTest, values, nil, -1)
 	if err != nil {