Set UpdateAutoCheckEnabled default to true, don't explicitly set a li…

…nk color for the update available text (red on white is hard to read, default is usually blue, which looks fine here)

src/BizHawk.Client.Common/config/Config.cs

@@ -164,7 +164,7 @@ public void SetWindowScaleFor(string sysID, int windowScale)
 		public bool AviCaptureLua { get; set; }
 		public bool ScreenshotCaptureOsd { get; set; }
 		public bool FirstBoot { get; set; } = true;
-		public bool UpdateAutoCheckEnabled { get; set; }
+		public bool UpdateAutoCheckEnabled { get; set; } = true;
 		public DateTime? UpdateLastCheckTimeUtc { get; set; }
 		public string UpdateLatestVersion { get; set; } = "";
 		public string UpdateIgnoreVersion { get; set; } = "";