Fix race in tcp_retransmits_test
Fix race in tcp_retransmits_test

The test queries for RTO via TCP_INFO and applies that to the
rest of the test. The RTO is estimated by processing incoming ACK.
There is a race in the test where we may query for RTO before the
incoming ACK was processed. Fix the race in the test by letting the
DUT complete a payload receive, thus estimating RTO before proceeding
to query the RTO. Bump up the time correction to reduce flakes.

PiperOrigin-RevId: 362865904

google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor