Currently we set `directConnection=true` on the connection model when we connect:
https://github.com/mongodb-js/connection-model/blob/master/lib/connect.js#L228
With playgrounds the connection options we pass do not currently . This is to ensure that any connections using that connection model which don't use that connect method, like compass-shell or vscode playgrounds also have `directConnection=true`.

When `directConnection` is already set on the connection model we should not override it.

In mongodb node driver v4.0 this change around not setting `directConnection=true` when connecting will land. The driver 3.6.3 version prematurely added this change which was reverted in 3.6.4: https://github.com/mongodb/node-mongodb-native/commit/617d9dec5180c5f7b67bd8c944c168d4cbd27e1c 

This impacts the playground runtime.
Related github issue: https://github.com/mongodb-js/vscode/issues/249