Merge pull request #5765 from TylerMSFT/xamarin

remove xamarin

Author: prmerger-automator[bot]

docs/index.yml

@@ -1,7 +1,7 @@
 ### YamlMime:Hub
 title: Microsoft C++, C, and Assembler documentation
 summary: Learn how to use C++, C, and assembly language to develop applications, services, and tools for your platforms and devices.
-# brand: aspnet | azure | dotnet | dynamics | m365 | ms-graph | office | power-platform | sql | sql-server | vs | visual-studio | windows | xamarin
+# brand: aspnet | azure | dotnet | dynamics | m365 | ms-graph | office | power-platform | sql | sql-server | vs | visual-studio | windows
 brand: visual-studio
 metadata:
   title: Microsoft C/C++ Documentation