Reenable helix project platforms

Author: HaoK

src/Components/test/E2ETest/Microsoft.AspNetCore.Components.E2ETests.csproj

@@ -61,7 +61,6 @@
     <HelixContent Include="yarn.lock" />
     <!-- This is currently windows only -->
     <HelixProjectPlatform Remove="Linux;OSX" />
-    <HelixProjectPlatform Remove="@(HelixProjectPlatform)" />    
     <HelixProjectTargetQueue Include="Windows.10.Amd64.ClientRS4.VS2017.Open" />
   </ItemGroup>