[internal/release/5.0-preview8] Update dependencies from dnceng/internal/dotnet-winforms

- Updates:
  - Microsoft.Private.Winforms: from 5.0.0-preview.8.20402.4 to 5.0.0-preview.8.20406.4

Author: dotnet-bot

eng/Version.Details.xml

@@ -1,9 +1,9 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Dependencies>
   <ProductDependencies>
-    <Dependency Name="Microsoft.Private.Winforms" Version="5.0.0-preview.8.20402.4">
+    <Dependency Name="Microsoft.Private.Winforms" Version="5.0.0-preview.8.20406.4">
       <Uri>https://dev.azure.com/dnceng/internal/_git/dotnet-winforms</Uri>
-      <Sha>f560e76b0ca6a42a628986e3c2e267a8a772ec68</Sha>
+      <Sha>f1d17de636f280d279b3fb24a725b0bcd1d23186</Sha>
     </Dependency>
     <Dependency Name="Microsoft.Win32.Registry" Version="5.0.0-preview.8.20381.10" CoherentParentDependency="Microsoft.Private.Winforms">
       <Uri>https://github.com/dotnet/runtime</Uri>

eng/Versions.props

@@ -9,7 +9,7 @@
   </PropertyGroup>
   <!-- NuGet Package Versions -->
   <PropertyGroup>
-    <MicrosoftPrivateWinformsVersion>5.0.0-preview.8.20402.4</MicrosoftPrivateWinformsVersion>
+    <MicrosoftPrivateWinformsVersion>5.0.0-preview.8.20406.4</MicrosoftPrivateWinformsVersion>
   </PropertyGroup>
   <!-- Packages that come from https://github.com/dotnet/coreclr -->
   <PropertyGroup>