Include link to gum documentation

Author: AristurtleDev

articles/tutorials/building_2d_games/20_implementing_ui_with_gum/index.md

@@ -353,7 +353,7 @@ To add the Gum NuGet package using the dotnet CLI:
 > ```
 
 > [!IMPORTANT]
-> This tutorial uses version `2025.5.5.1` of Gum, which is the latest version of Gum as of this writing.  That exact version is specified to use in the section above when installing the NuGet package to ensure compatibility throughout this tutorial.  If there are newer versions of Gum available, please consult the Gum documentation before updating in case there are any breaking changes from the code that is presented in this tutorial.
+> This tutorial uses version `2025.5.5.1` of Gum, which is the latest version of Gum as of this writing.  That exact version is specified to use in the section above when installing the NuGet package to ensure compatibility throughout this tutorial.  If there are newer versions of Gum available, please consult the [Gum documentation](https://docs.flatredball.com/gum/gum-tool/breaking-changes) before updating in case there are any breaking changes from the code that is presented in this tutorial.
 
 ### Adding UI Sound Effect