test: Fix O(1/32k) flakiness in H2 flood tests that disable writes based on source port of outgoing connections. (#14695)
test: Fix O(1/32k) flakiness in H2 flood tests that disable writes based on source port of outgoing connections. (#14695)

It is possible for the kernel to assign the same source port to both the client connection used by
the test framework to connect to the Envoy and the Envoy's client connection to the upstream. When
the source port is reused by both connections, the test client times out while trying to send the
request because disabling write on the upstream connection also disabled writes on the test's client
connection.

Signed-off-by: Antonio Vicente <3264b79815f9dfda4d4b4e4281b8e33e1075040b@google.com>
envoyproxy/envoy,lyft/envoy,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy,lyft/envoy,envoyproxy/envoy,lyft/envoy,envoyproxy/envoy,envoyproxy/envoy,lyft/envoy,lyft/envoy,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy,lyft/envoy