Improve the GoogleDrive Downloader a bit

Wabbajack.Lib/Http/HttpExtensions.cs

@@ -0,0 +1,22 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net.Http;
+
+namespace Wabbajack.Lib.Http
+{
+    public static class HttpExtensions
+    {
+        public static IEnumerable<(string Key, string Value)> GetSetCookies(this HttpResponseMessage response)
+        {
+            if (!response.Headers.TryGetValues("set-cookie", out var values))
+                return Array.Empty<(string, string)>();
+            
+            return values
+                .SelectMany(h => h.Split(";"))
+                .Select(h => h.Split("="))
+                .Where(h => h.Length == 2)
+                .Select(h => (h[0], h[1]));
+        }
+    }
+}