nuget update

Author: arturcic

src/GitVersionTask.MsBuild/GitVersionTask.MsBuild.csproj

@@ -8,7 +8,7 @@
     <ItemGroup>
         <PackageReference Include="Microsoft.Build" Version="16.3.0" />
         <PackageReference Include="Microsoft.Build.Tasks.Core" Version="16.3.0" />
-        <PackageReference Include="Microsoft.DotNet.PlatformAbstractions" Version="3.0.1" />
+        <PackageReference Include="Microsoft.DotNet.PlatformAbstractions" Version="2.1.0" />
     </ItemGroup>
 
     <ItemGroup>