Update usage of AllowEmptyTelemetry based on changes to the task in the SDK (#82804)

Author: baronfel

src/tasks/Crossgen2Tasks/Microsoft.NET.CrossGen.targets

@@ -346,7 +346,13 @@ Copyright (c) .NET Foundation. All rights reserved.
                             _CreateR2RImages;
                             _CreateR2RSymbols">
 
-    <AllowEmptyTelemetry EventName="ReadyToRun" EventData="PublishReadyToRunUseCrossgen2=$(PublishReadyToRunUseCrossgen2);Crossgen2PackVersion=%(ResolvedCrossgen2Pack.NuGetPackageVersion);CompileListCount=@(_ReadyToRunCompileList->Count());FailedCount=@(_ReadyToRunCompilationFailures->Count())" />
+    <ItemGroup>
+       <_R2RCrossgenTelemetry Include="PublishReadyToRunUseCrossgen2" Value="$(PublishReadyToRunUseCrossgen2)" />
+       <_R2RCrossgenTelemetry Include="Crossgen2PackVersion" Value="%(ResolvedCrossgen2Pack.NuGetPackageVersion)" />
+       <_R2RCrossgenTelemetry Include="CompileListCount" Value="@(_ReadyToRunCompileList->Count())" />
+       <_R2RCrossgenTelemetry Include="FailedCount" Value="@(_ReadyToRunCompilationFailures->Count())" />
+    </ItemGroup>
+    <AllowEmptyTelemetry EventName="ReadyToRun" EventData="@(_R2RCrossgenTelemetry)" />
 
     <NETSdkError Condition="'@(_ReadyToRunCompilationFailures)' != ''" ResourceName="ReadyToRunCompilationFailed" />
 
@@ -519,4 +525,4 @@ Copyright (c) .NET Foundation. All rights reserved.
                                       Include="@(_ReadyToRunSymbolsCompileList)" />
     </ItemGroup>
   </Target>
-</Project>
+</Project>