Fix docs/examples with cast_results() method on DSISClient

1. [example ](https://github.com/equinor/dsis-python-client/blob/85a7f70ac99d0da34849246c41fad2724d38cf40/src/dsis_client/api/query/builder.py#L32)suggesting it is a `query `method, while it is on `client`.
2. [this example](https://github.com/equinor/dsis-python-client/blob/85a7f70ac99d0da34849246c41fad2724d38cf40/src/dsis_client/api/client/_query.py#L187) suggests twice that the `response` has a `value` key, but I am getting a generator object from `client.executeQuery(query)`, so it is a bit misleading. Unless there can be different response types here?

Didn't check for more examples, but might be worth checking.