Configure the flow control algorithm for buffered uploads.
Buffered uploads flow control the sender if the internal buffer exceeds the HWM (High Watermark) value configured in this option. The flow control is only released once the internal buffer reaches the LWM (Low Watermark) value configured via BufferedUploadLwmOption.
The library caps these values as follows (1) the LWM is always capped to the [256KiB, std::numeric_limits<std::size_t>::max() / 4] range, and (2) the HWM is always at least two times the LWM.
