Add support for dotnet core for Windows

OpenRA.Test/OpenRA.Test.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFramework>net472</TargetFramework>
+    <TargetFramework>net5.0</TargetFramework>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <LangVersion>7.3</LangVersion>
     <DebugSymbols>true</DebugSymbols>
@@ -10,6 +10,7 @@
     <PlatformTarget>AnyCPU</PlatformTarget>
     <EnableDefaultCompileItems>false</EnableDefaultCompileItems>
     <CodeAnalysisRuleSet>..\OpenRA.ruleset</CodeAnalysisRuleSet>
+    <IsPublishable>false</IsPublishable>
   </PropertyGroup>
   <ItemGroup>
     <!-- Work around an issue where Rider does not detect files in the project root using the default glob -->
@@ -22,14 +23,12 @@
   <ItemGroup>
     <ProjectReference Include="..\OpenRA.Game\OpenRA.Game.csproj" />
     <ProjectReference Include="..\OpenRA.Mods.Common\OpenRA.Mods.Common.csproj">
-      <Private>False</Private>
+      <Private>True</Private>
     </ProjectReference>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.6.1" />
     <PackageReference Include="NUnit" Version="3.12.0" />
     <PackageReference Include="NUnit.Console" Version="3.11.1" />
-    <PackageReference Include="NUnit3TestAdapter" Version="3.16.1">
-      <PrivateAssets>all</PrivateAssets>
-      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
-    </PackageReference>
+    <PackageReference Include="NUnit3TestAdapter" Version="3.17.0-beta.1" />
     <PackageReference Include="StyleCop.Analyzers" Version="1.1.118" />
     <PackageReference Include="Microsoft.NETFramework.ReferenceAssemblies" Version="1.0.0" PrivateAssets="All" />
     <AdditionalFiles Include="../stylecop.json" />
@@ -40,4 +39,4 @@
       <Analyzer Remove="@(Analyzer)" />
     </ItemGroup>
   </Target>
-</Project>
+</Project>