!fixup! Normalize paths for Helix

- use `$(ArtifactsShippingPackagesDir)` in Helix.targets
- use `[MSBuild]::NormalizeDirectory(...)` and `$([System.IO.Path]::Combine(...)` in helix.proj

Author: dougbu

eng/helix/helix.proj

@@ -35,7 +35,8 @@
     <DotNetCliChannel>Current</DotNetCliChannel>
 
     <!-- Similar to ProjectLayout.props in the Arcade SDK. The Helix SDK contains nothing similar. -->
-    <OutputPath Condition=" '$(OutputPath)' == '' ">$(RepoRoot)artifacts\bin\$(MSBuildProjectName)\</OutputPath>
+    <OutputPath Condition=" '$(OutputPath)' == '' "
+        >$([MSBuild]::NormalizeDirectory('$(RepoRoot)', 'artifacts', 'bin', '$(MSBuildProjectName)'))</OutputPath>
   </PropertyGroup>
 
   <!-- Specify the .NET runtime we need which will be included as a correlation payload. -->
@@ -97,10 +98,10 @@
 
     <PropertyGroup>
       <SharedFxVersion>@(_ResolvedProductVersionInfo->'%(PackageVersion)')</SharedFxVersion>
-      <_AppRefSubPath>packs\Microsoft.AspNetCore.App.Ref\$(SharedFxVersion)</_AppRefSubPath>
-      <_AppRuntimeSubPath>shared\Microsoft.AspNetCore.App\$(SharedFxVersion)</_AppRuntimeSubPath>
-      <_AppRefPath>$(RepoRoot).dotnet\$(_AppRefSubPath)</_AppRefPath>
-      <_AppRuntimePath>$(RepoRoot).dotnet\$(_AppRuntimeSubPath)</_AppRuntimePath>
+      <_AppRefSubPath>$([System.IO.Path]::Combine('packs', 'Microsoft.AspNetCore.App.Ref', '$(SharedFxVersion)'))</_AppRefSubPath>
+      <_AppRuntimeSubPath>$([System.IO.Path]::Combine('shared', 'Microsoft.AspNetCore.App', '$(SharedFxVersion)'))</_AppRuntimeSubPath>
+      <_AppRefPath>$([MSBuild]::NormalizeDirectory('$(RepoRoot)', '.dotnet', '$(_AppRefSubPath)'))</_AppRefPath>
+      <_AppRuntimePath>$([MSBuild]::NormalizeDirectory('$(RepoRoot)', '.dotnet', '$(_AppRuntimeSubPath)'))</_AppRuntimePath>
 
       <!--
         Don't bother checking for App.Runtime layout because we want both and App.Ref project depends on the

eng/targets/Helix.targets

@@ -60,12 +60,10 @@
   -->
   <ItemGroup>
     <!-- Grab all shipping packages. -->
-    <HelixContent
-        Include="$(RepoRoot)artifacts\packages\$(Configuration)\Shipping\*$(SharedFxVersion).nupkg"
+    <HelixContent Include="$(ArtifactsShippingPackagesDir)*$(SharedFxVersion).nupkg"
         Condition=" $(TestDependsOnAspNetPackages) "/>
     <!-- Grab just the App.Ref and App.Runtime packages. -->
-    <HelixContent
-        Include="$(RepoRoot)artifacts\packages\$(Configuration)\Shipping\Microsoft.AspNetCore.App.*$(SharedFxVersion).nupkg"
+    <HelixContent Include="$(ArtifactsShippingPackagesDir)Microsoft.AspNetCore.App.*$(SharedFxVersion).nupkg"
         Condition=" $(TestDependsOnAspNetAppPackages) "/>
   </ItemGroup>