Update gVisor to include its fix for RACK loss detection with coarse
monotonic clocks. Configure netstack with the 500 microsecond clock
resolution used on Windows so RACK accounts for timestamp quantization.
Remove the TCP recovery override that disabled RACK, enabling gVisor's
default RACK behavior on all platforms.
Switch netstack to cubic congestion control. The int overflow in CUBIC
sender cwnd arithmetic that required pinning reno has since been reworked
upstream into float arithmetic with RFC 9438 target clamping.
Align the natlab vnet stack with netstack: enable cubic, and drop the
now-redundant explicit SACK and receive-buffer moderation sets, both of
which are gVisor defaults.
Fixes#9707
Signed-off-by: James Tucker <jftucker@gmail.com>
James Tucker
3ec674bc86