In the example below, we can see that `col1.first` reads from port 20001 (secondary) and that's considered correct. After we clone col1, pretty print shows same options (notice `:mode` becoming `"mode"`), but `col1.clone.first` reads from port 20000, which is assigned to the primary. The same thing happens if we do `col1.where(anything)` since `.where` internally clones the selection.

```ruby
[152] app(PROD)> col1
=> #<Mongoid::Criteria
selector:

{"app_id"=>6}
options: {:read=>{:mode=>:secondary}}
class: External::User
embedded: false>
[153] app(PROD)> col1.first;
MONGODB | 127.0.0.1:20001 | production_users_2.find | STARTED | {"find"=>"users", "filter"=>{"app_id"=>6}

, "limit"=>1, "singleBatch"=>true}
MONGODB | 127.0.0.1:20001 | production_users_2.find | SUCCEEDED | 0.0020012600000000004s
[155] app(PROD)> col1.clone
=> #<Mongoid::Criteria
selector:

{"app_id"=>6}
options: {:read=>{"mode"=>:secondary}}
class: External::User
embedded: false>
[156] app(PROD)> col1.clone.first
MONGODB | 127.0.0.1:20000 | production_users_2.find | STARTED | {"find"=>"users", "filter"=>{"app_id"=>6}

, "limit"=>1, "singleBatch"=>true}
MONGODB | 127.0.0.1:20000 | production_users_2.find | SUCCEEDED | 0.002215638s
```