test: deflake by making registerTestServerPorts thread safe (#10523)
test: deflake by making registerTestServerPorts thread safe (#10523)

The is data race, reported by tsan
The root cause is listener manager is accessed in both envoy master thread and test thread.
Use Dispatcher::post to access ListenerManager::listeners()

Signed-off-by: Yuchen Dai <f2550135201283870cb3c3d0a55f74b43525a4a1@gmail.com>
envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy,istio/envoy,envoyproxy/envoy-wasm,lizan/envoy,istio/envoy,envoyproxy/envoy-wasm,istio/envoy,istio/envoy,envoyproxy/envoy,envoyproxy/envoy-wasm,envoyproxy/envoy,lizan/envoy,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy-wasm,istio/envoy,envoyproxy/envoy,lizan/envoy,lizan/envoy,istio/envoy,lyft/envoy,envoyproxy/envoy-wasm,lyft/envoy,envoyproxy/envoy,lizan/envoy,lyft/envoy,envoyproxy/envoy-wasm,envoyproxy/envoy-wasm,envoyproxy/envoy,lyft/envoy,lizan/envoy,lyft/envoy,envoyproxy/envoy,lyft/envoy,istio/envoy