txn_override.js shouldn't have a write concern when creating a collection outside of a transaction

In txn_override.js, if an insert attempts to do implicit collection creation inside a transaction, we will abort the transaction, create the collection outside of a transaction, and retry the transaction. If the collection creation fails with a write concern error, it will fail here and we'll then retry the create collection. This can cause an error because it means we could retry the collection creation even though it already succeeded the first time.