Publishing fixup for .Debug builds (#2529)

* Bring publishing.props from WpfArcadeSdk into publish.proj's environment

* Improve ArcadeWpfSdk import logic

* Remove spurious =

* Fix typo

* Versions.props is imported by Arcade directly - do not import again

* Import only publishing related props/targets

* ArtifactsTmpDir Can only be updated when it is non-empty

* Use the right version var

* Use the right version

eng/Publishing.props

+<Project>
+  <!-- 
+    Publishing.props from WPF's build props will be imported here directly during publishing
+    
+    Use the published SDK from NuGet if available, or local files otherwise. 
+    -->
+  <Import Sdk="Microsoft.DotNet.Arcade.Wpf.Sdk" 
+          Version="$(MicrosoftDotNetArcadeWpfSdkVersion)"
+          Project="..\tools\Publishing.props"
+          Condition="'$(MicrosoftDotNetArcadeWpfSdkVersion)' != ''"/>
+  <Import Sdk="Microsoft.DotNet.Arcade.Wpf.Sdk" 
+          Version="$(MicrosoftDotNetArcadeWpfSdkVersion)"
+          Project="..\tools\Publishing.targets"
+          Condition="'$(MicrosoftDotNetArcadeWpfSdkVersion)' != ''"/>
+
+  <Import Project="WpfArcadeSdk\tools\Publishing.props"
+          Condition="'$(MicrosoftDotNetArcadeWpfSdkVersion)' == '' And 
+                      Exists('WpfArcadeSdk\Sdk\Sdk.props') And Exists('WpfArcadeSdk\Sdk\Sdk.targets')"/>
+  <Import Project="WpfArcadeSdk\tools\Publishing.targets"
+        Condition="'$(MicrosoftDotNetArcadeWpfSdkVersion)' == '' And 
+                      Exists('WpfArcadeSdk\Sdk\Sdk.props') And Exists('WpfArcadeSdk\Sdk\Sdk.targets')"/>
+</Project>

eng/WpfArcadeSdk/tools/FolderPaths.props

 <Project>
-  <PropertyGroup>
+  <PropertyGroup Condition="'$(ArtifactsTmpDir)' != '' And '$(Architecture)' != ''">
     <!--
       Append Platform to $(ArtifactsTmpDir)
     -->