[main] [release/9.0.1xx-sr8] Fix signing of fonts with arcade infra (#30938)

Backport of #30937 to main

/cc @rmarinho

Author: rmarinho

eng/Signing.props

@@ -29,6 +29,7 @@
     <FileExtensionSignInfo Update=".nupkg" CertificateName="NuGet" />
     <FileExtensionSignInfo Update=".zip" CertificateName="None" />
     <FileExtensionSignInfo Include=".msi" CertificateName="MicrosoftDotNet500" />
+    <FileExtensionSignInfo Include=".ttf" CertificateName="Microsoft400" />
   </ItemGroup>
 
   <ItemGroup>