Check for a valid repository Url for Git Repositort Button Nest

Author: Reavert

VisualStudioDiscordRPC.Shared/Nests/Base/BaseButtonNest.cs

@@ -31,15 +31,17 @@ private void UpdateButtonWithInfo(int index, ButtonInfo buttonInfo)
                 default: throw new ArgumentOutOfRangeException($"{nameof(index)} must be 0 or 1");
             }
 
-            if (string.IsNullOrEmpty(buttonInfo.Label) || string.IsNullOrEmpty(buttonInfo.Url))
+            if (string.IsNullOrEmpty(buttonInfo.Label) || 
+                string.IsNullOrEmpty(buttonInfo.Url) || 
+                Uri.TryCreate(buttonInfo.Url, UriKind.Absolute, out Uri _))
             {
                 Buttons.Remove(button);
                 return;
             }
 
             button.Label = buttonInfo.Label;
             button.Url = buttonInfo.Url;
-
+            
             if (!Buttons.Contains(button))
             {
                 Buttons.Add(button);