[libraries] Fix metadata name following arcade change to stop supporting...

[libraries] Fix metadata name following arcade change to stop supporting multiple targets in helix sdk (#53828)
Co-authored-by: NMitchell Hwang <mitchell.hwang@microsoft.com>

src/libraries/sendtohelixhelp.proj

@@ -260,7 +260,7 @@
     <ItemGroup Condition="'$(TargetOS)' == 'iOS' or '$(TargetOS)' == 'tvOS' or '$(TargetOS)' == 'iOSSimulator' or '$(TargetOS)' == 'tvOSSimulator' or '$(TargetOS)' == 'MacCatalyst'">
       <!-- Create work items for test apps -->
       <XHarnessAppBundleToTest Include="$([System.IO.Directory]::GetDirectories('$(TestArchiveTestsRoot)', '*.app', System.IO.SearchOption.AllDirectories))">
-        <Targets>$(AppleTestTarget)</Targets>
+        <TestTarget>$(AppleTestTarget)</TestTarget>
       </XHarnessAppBundleToTest>
       <!-- Create work items for run-only apps -->
       <XHarnessAppBundleToTest Condition="Exists('$(TestArchiveRoot)runonly')" Include="$([System.IO.Directory]::GetDirectories('$(TestArchiveRoot)runonly', '*.app', System.IO.SearchOption.AllDirectories))" >
@@ -268,7 +268,7 @@
         <IncludesTestRunner>false</IncludesTestRunner>
         <!-- The sample's C# Main method returns 42 so it should be considered by xharness as a success -->
         <ExpectedExitCode>42</ExpectedExitCode>
-        <Targets>$(AppleTestTarget)</Targets>
+        <TestTarget>$(AppleTestTarget)</TestTarget>
       </XHarnessAppBundleToTest>
     </ItemGroup>