Wait for the future response

[marcvdm]

The current SniffingConnectionPool uses the sniff method on the Connection class but this needs to return an array. The current implementation fails because a future request is returned.

This merge requests adds the wait function for the return.

[ezimuel]

The Connection::performRequest() returns a mixed type. When I did the code refactoring, introducing type hints and return types, I struggled between the old implementation and the new one.
Maybe a better idea is to remove the return type on the sniff() function, in order to preserve asynchronous feature. What do you think? Thanks for reporting this issue.

[marcvdm]

I'v updated the pull request and remove the typehints. This way the response can be an array or FutureArray and the parseClusterState wil iterate over an array or ArrayAccess variable

[ezimuel]

Thanks @marcvdm