import dir.targets in CoreClr 2.0.0 (#18351)

Author: wtgodbe

src/publish.proj

@@ -3,6 +3,7 @@
   <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildThisFileDirectory), dir.props))\dir.props" />
   <Import Project="$(ToolsDir)PublishContent.targets" />
   <Import Project="$(ToolsDir)versioning.targets" />
+  <Import Project="..\dir.targets" />
 
   <!-- gathers the items to be published -->
   <Target Name="GatherItemsForPattern">