React to NuGet package pruning warnings

Contributes to dotnet/sdk#46642

NuGet added a new feature that automatically prunes package and project references that are provided by the shared framework that is targeted.

React to two warnings that got flagged when building the product source-only.

Author: ViktorHofer

src/Microsoft.TestPlatform.CoreUtilities/Microsoft.TestPlatform.CoreUtilities.csproj

@@ -17,11 +17,8 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.Win32.Registry" Version="$(MicrosoftWin32RegistryVersion)" Condition=" '$(TargetFramework)' == 'netstandard2.0' " />
-  </ItemGroup>
-
-  <ItemGroup>
-    <PackageReference Include="System.Reflection.Metadata" Version="$(SystemReflectionMetadataVersion)" />
+    <PackageReference Include="Microsoft.Win32.Registry" Version="$(MicrosoftWin32RegistryVersion)" Condition="'$(TargetFramework)' == 'netstandard2.0'" />
+    <PackageReference Include="System.Reflection.Metadata" Version="$(SystemReflectionMetadataVersion)" Condition="'$(TargetFrameworkIdentifier)' != '.NETCoreApp'" />
   </ItemGroup>
 
   <ItemGroup>

src/Microsoft.TestPlatform.ObjectModel/Microsoft.TestPlatform.ObjectModel.csproj

@@ -35,9 +35,8 @@
   <ItemGroup>
     <!-- net48 includes tuple, we need to reference it in previous versions but only on .net framework. -->
     <PackageReference Include="System.ValueTuple" Version="4.5.0" 
-        Condition="$([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net48')) != true
-                    and $([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net4'))" />
-    <PackageReference Include="System.Reflection.Metadata" Version="$(SystemReflectionMetadataVersion)" />
+        Condition="$([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net48')) != 'true' and '$(TargetFrameworkIdentifier)' == '.NETFramework'" />
+    <PackageReference Include="System.Reflection.Metadata" Version="$(SystemReflectionMetadataVersion)" Condition="'$(TargetFrameworkIdentifier)' != '.NETCoreApp'" />
   </ItemGroup>
 
   <ItemGroup>