Force QueryClient to use HTTP Auth for N1QL queries

Temp fix for: MB-16964

Note that QueryRequest.AddCredentials will not work until MB-16964 is resolved. This fix will use the credentials passed into Cluster.OpenBucket(user, pass) as the N1QL query credentials, adding them to the HTTP header, and sent the server.

• If the bucket name in the query does not match the the bucket that was opened and auth'd, then the query will failed with "Authorization Failed"
• If you try to use QueryRequest.AddCredentials, you will receive "creds has to be of type array of { user, pass }

  "

Once MB-16964 is released as a server fix, AddCredentials will work for all versions of the server in which the fix applies-for server versions 4.0.0, etc this work around will apply.