New3 broken build

My build was failing with "no definition for ExecuteGetRequest" here: https://github.com/ayende/ravendb/blob/New3/Bundles/Raven.Client.Authorization/AuthorizationClientExtensions.cs#L45

It looks like it got deleted in this commit:
https://github.com/ayende/ravendb/commit/fc054a79dd3bfe49edc5e2057481383d7340b387

Added it back following the style form the above commit.