Unskip AsyncInCatchFilter

[JoeRobich]

In the move from running against .NET 10 to .NET 11 preview, the following async runtime test failure was encountered:

CodeGenAsyncEHTests.AsyncInCatchFilter

System.AggregateException : One or more errors occurred. (Object reference not set to an instance of an object.)
---- System.NullReferenceException : Object reference not set to an instance of an object.



Stack trace
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at Test.Main() in :line 40
   at System.RuntimeMethodHandle.InvokeMethod(ObjectHandleOnStack target, Void** arguments, ObjectHandleOnStack sig, BOOL isConstructor, ObjectHandleOnStack result)
   at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)
----- Inner Stack Trace -----
   at Test.G() in :line 32
   at System.Runtime.CompilerServices.AsyncHelpers.RuntimeAsyncTask`1.DispatchContinuations()

[333fred]

This appears to be a runtime-async bug in .NET 11 Preview 6. I reduced the test to the following file-based app:

#:property Features=runtime-async=on
#:property LangVersion=preview
#:property Optimize=true
#:property NoWarn=SYSLIB5007;CA2252

using System;
using System.Threading.Tasks;

Test.Run().GetAwaiter().GetResult();

class Test
{
    public static async Task Run()
    {
        try
        {
            throw new Exception();
        }
        catch (Exception caught) when ((caught = new Exception("success")) != null)
        {
            await Task.Yield();
            Console.WriteLine(caught.Message);
        }
    }
}

With global.json pinned to SDK 10.0.301, this exits successfully:

$ DOTNET_RuntimeAsync=1 dotnet run 84792.cs
success

With global.json pinned to SDK 11.0.100-preview.6.26359.118, the same command fails because the exception variable assigned by the filter becomes null after the await:

$ dotnet run 84792.cs
Unhandled exception. System.NullReferenceException: Object reference not set to an instance of an object.
   at Test.Run() in 84792.cs:line 22

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