Updating vsmac download link

Author: sayedihashimi

mac/installation.md

@@ -13,7 +13,7 @@ ms.custom: video
 To start developing native, cross-platform .NET apps on macOS, install Visual Studio 2019 for Mac following the steps below.
 
  > [!div class="button"]
- > [Download Visual Studio for Mac](https://visualstudio.microsoft.com/downloads/?utm_medium=microsoft&utm_source=docs.microsoft.com&utm_campaign=navigation+cta&utm_content=download+vsmac2019)
+ > [Download Visual Studio for Mac](https://aka.ms/vsmac)
 
 ## Requirements