[deployment] change health check endpoint to 4000

bin/deployment/health_check

@@ -7,7 +7,7 @@ timeout 120s bash <<EOT
 # Wait until an HTTP request succeeds against localhost:PORT
 function ping_server(){
     while true; do
-        if curl -sSf "http://localhost:${PORT:-80}" >/dev/null; then
+        if curl -sSf "http://localhost:4000" >/dev/null; then
             exit 0
         fi
     done