Use older nuget packages for netstandard2.0 target.

src/BenchmarkDotNet/BenchmarkDotNet.csproj

@@ -22,19 +22,21 @@
     <PackageReference Include="Iced" Version="1.17.0" />
     <PackageReference Include="Microsoft.Diagnostics.Runtime" Version="2.2.332302" />
     <PackageReference Include="Perfolizer" Version="0.2.1" />
-    <PackageReference Include="System.Management" Version="6.0.0" />
-    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.5.0" />
     <PackageReference Include="Microsoft.Diagnostics.Tracing.TraceEvent" Version="3.0.2" PrivateAssets="contentfiles;analyzers" />
     <PackageReference Include="Microsoft.DotNet.PlatformAbstractions" Version="3.1.6" />
   </ItemGroup>
-  <ItemGroup Condition=" '$(TargetFrameworkIdentifier)' == '.NETStandard' ">
+  <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard2.0' ">
     <PackageReference Include="Microsoft.Win32.Registry" Version="5.0.0" />
     <PackageReference Include="System.Numerics.Vectors" Version="4.5.0" />
-  </ItemGroup>
-  <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard2.0' ">
     <PackageReference Include="System.Reflection.Emit" Version="4.7.0" />
     <PackageReference Include="System.Reflection.Emit.Lightweight" Version="4.7.0" />
     <PackageReference Include="System.Threading.Tasks.Extensions" Version="4.5.4" />
+    <PackageReference Include="System.Management" Version="5.0.0" />
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.2.0" />
+  </ItemGroup>
+  <ItemGroup Condition=" '$(TargetFramework)' == 'net6.0' ">
+    <PackageReference Include="System.Management" Version="6.0.0" />
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.5.0" />
   </ItemGroup>
   <ItemGroup Condition="'$(OS)' == 'Windows_NT' AND '$(UseMonoRuntime)' != 'true' ">
     <ProjectReference Include="..\BenchmarkDotNet.Disassembler.x64\BenchmarkDotNet.Disassembler.x64.csproj">