Enable partial ngen for workspaces

Author: genlu

src/Workspaces/Core/Portable/Microsoft.CodeAnalysis.Workspaces.csproj

@@ -8,6 +8,7 @@
     <TargetFrameworks>netcoreapp3.1;netstandard2.0</TargetFrameworks>
     <DefineConstants>$(DefineConstants);WORKSPACE</DefineConstants>
     <GeneratePerformanceSensitiveAttribute>true</GeneratePerformanceSensitiveAttribute>
+    <ApplyNgenOptimization>partial</ApplyNgenOptimization>
 
     <!-- NuGet -->
     <IsPackable>true</IsPackable>