Fixes #2335

The `ReleaseNotes` struct has been replaced with an extension on URL. Release Notes can now be opened on all versions of NNW.

Multiplatform/Shared/Release Notes/ReleaseNotes.swift

@@ -10,6 +10,7 @@ import Foundation
 
 struct ReleaseNotes {
 	
+	@available(*, unavailable, message: "Use URL.releaseNotes")
 	var url: URL {
 		var gitHub = "https://github.com/Ranchero-Software/NetNewsWire/releases/tag/"
 		#if os(macOS)

Multiplatform/iOS/Settings/SettingsModel.swift

@@ -31,7 +31,7 @@ class SettingsModel: ObservableObject {
 			case .netNewsWireSlack:
 				return URL(string: "https://ranchero.com/netnewswire/slack")!
 			case .releaseNotes:
-				return ReleaseNotes().url
+				return URL.releaseNotes
 			case .none:
 				return nil
 			}