[Design] missing one

Xamarin.Forms.Xaml.Design/Xamarin.Forms.Xaml.Design.csproj

@@ -9,7 +9,7 @@
     <AppDesignerFolder>Properties</AppDesignerFolder>
     <RootNamespace>Xamarin.Forms.Xaml.Design</RootNamespace>
     <AssemblyName>Xamarin.Forms.Xaml.Design</AssemblyName>
-    <TargetFrameworkVersion>v4.7</TargetFrameworkVersion>
+    <TargetFrameworkVersion>v4.5</TargetFrameworkVersion>
     <FileAlignment>512</FileAlignment>
     <NuGetPackageImportStamp>
     </NuGetPackageImportStamp>