The Tory exodus from Westminster continued last night as Northern Ireland Secretary Chris Heaton-Harris announced he will not stand at the next general election. Heaton-Harris, who has served in the role since September 2022, put his plans to paper in a letter to beleagured Prime Minister Rishi Sunak. In the letter, the Daventry MP wrote: “Working with you I helped negotiate and deliver the Windsor Framework, which both solved many of the major practical issues created by the Northern Ireland Protocol, put in place as we left the EU, and helped reset our countries’ relationship with our Europe…