What problem are you facing?

mongo client have autoconnect on operation which introduced a bug when you can create multiple connections by executing multiple operations and not awaiting them.

without `await client.connect()`, the following code will create 5 internal `client.connect() `executions:
```
client.db("admin").command({ ping: 1 });
client.db("admin").command({ ping: 1 });
client.db("admin").command({ ping: 1 });
client.db("admin").command({ ping: 1 });
client.db("admin").command({ ping: 1 });
```
 
here is the code that will create a new connection . It will be executed 5 times.
Inside client.connect function there is an await which prevents   if (client.topology == null) { to omit reconnecting. 
 

this is a code that sets client.topology 

and this is await which prevents setting that client.topology 

mongodb@5.5.0 has a connection lock which fixes the issue completely https://github.com/mongodb/node-mongodb-native/blob/v5.5.0/src/mongo_client.ts#L418

it should be backported to mongodb@4

this issue caused a bug in Meteor https://github.com/meteor/meteor/issues/12642#issuecomment-1567398407

What driver and relevant dependency versions are you using?

"mongodb": "4.16.0"

Steps to reproduce?

1. create cloud.mongodb.com free tier cluster
2. clone github.com/yrambler2001/mongodb-4.16-connections-bug 
3. open works-bad.js and works-well.js and change connection string to cluster created in step 1. KEEP THE mongodb+srv PART AND &maxPoolSize=100&minPoolSize=100 PART
4. npm run start-bad,
5. after 1-2 minutes, on the cloud.mongodb.com you can see 300-500 connections
6. npm run start-ok
7. after 1-2 minutes, on the cloud.mongodb.com you can see 100 connections

https://youtu.be/WmdRn7h2HdM