add congestion control test to CTS

This is not a substantially new test, as VTS has already required
either reno or cubic, and reno is ancient and obsolete (and was
only ever included because it's builtin to the kernel), so in
practice everything should have already always been using cubic.

Bug: 281477097
Test: TreeHugger, atest ProcNetTest
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I04622ae37265361f648bbcf46c0a10e22be3b24f
1 file changed