Update dependencies from https://github.com/dotnet/winforms build 20200401.2 (dotnet#2834)

- Microsoft.Private.Winforms - 5.0.0-preview.4.20201.2

Co-authored-by: dotnet-maestro[bot] <dotnet-maestro[bot]@users.noreply.github.com>

Author: dotnet-maestro[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.4.20201.3">
+    <Dependency Name="Microsoft.Private.Winforms" Version="5.0.0-preview.4.20201.2">
       <Uri>https://github.com/dotnet/winforms</Uri>
-      <Sha>69f0480456b5273b6acbbd3e8393ca8432420fd8</Sha>
+      <Sha>b45c16e905aadce7bb61945395cd0751680f9781</Sha>
     </Dependency>
   </ProductDependencies>
   <ToolsetDependencies>

eng/Versions.props

@@ -9,7 +9,7 @@
   </PropertyGroup>
   <!-- NuGet Package Versions -->
   <PropertyGroup>
-    <MicrosoftPrivateWinformsVersion>5.0.0-preview.4.20201.3</MicrosoftPrivateWinformsVersion>
+    <MicrosoftPrivateWinformsVersion>5.0.0-preview.4.20201.2</MicrosoftPrivateWinformsVersion>
   </PropertyGroup>
   <!-- Packages that come from https://github.com/dotnet/coreclr -->
   <PropertyGroup>