fix(connect): correct replacement of topology on connect callback

if topology.connect has an error, topology is "overwritten", changing the function parameter to a new name, let's "force close" the old instance.

Author: simllll

lib/operations/mongo_client_ops.js

@@ -407,14 +407,14 @@ function createTopology(mongoClient, topologyType, options, callback) {
   relayEvents(mongoClient, topology);
 
   // Open the connection
-  topology.connect(options, (err, topology) => {
+  topology.connect(options, (err, newTopology) => {
     if (err) {
       topology.close(true);
       return callback(err);
     }
 
-    assignTopology(mongoClient, topology);
-    callback(null, topology);
+    assignTopology(mongoClient, newTopology);
+    callback(null, newTopology);
   });
 }