Exceptions Aren't Thrown For N1QL Errors After Results

When errors occur after the "results" portion of the N1QL query response, no exception is thrown. This is rare, but can happen if the server encounters a problem after result streaming begins.

Additionally, it seems to consistently happen if the error is related to RBAC:

{

    "requestID": "033651a5-4138-4617-9bb6-6e0e0d0eb218",

    "signature": {

        "*": "*"

    },

    "results": [],

    "errors": [

        {

            "code": 13014,

            "msg": "User does not have credentials to run SELECT queries on the default bucket. Add role query_select on default to allow the query to run."

        }

    ],

    "status": "fatal",

    "metrics": {

        "elapsedTime": "7.574158ms",

        "executionTime": "7.510357ms",

        "resultCount": 0,

        "resultSize": 0,

        "errorCount": 1

    }

}

I recommend two changes:

1. After we get done iterating through the list, check for errors and throw an exception if they are found for consistency
2. If possible, detect the empty result array case early so we can throw the exception before the result set is iterated

Forum post: https://forums.couchbase.com/t/cannot-execute-n1ql-queries-with-couchbase-net-sdk-3-0/27707/8