close server connections in test cleanup

avoids timing out sockets between tests on node<19

Author: minrk

lib/testutil.js

@@ -149,5 +149,8 @@ exports.teardownServers = function (callback) {
   };
   for (var i = servers.length - 1; i >= 0; i--) {
     servers[i].close(onclose);
+    // closeAllConnections is implied in close in node >=19
+    // but this avoids waits between all tests with node 18
+    servers[i].closeAllConnections();
   }
 };