[Bug]: TransformWithInlineUpdate changes ChangeReason.Update to ChangeReason.Refresh

[SharpDevSa]

Describe the bug 🐞

The TransformWithInlineUpdate operator changes the incoming change with change reason Update to reason Refresh, which ruins binary search in SortAndBind, SortAndVertualize, etc.

Is is expected?

Step to reproduce

public class TransformWithInlineUpdateTest : ReactiveTest
{
    [Fact]
    public void AfterTransformRemainsUpdate()
    {
        TestScheduler testScheduler = new();
        SourceCache<string, string> sourceCache = new(x => x);

        IObservable<IChangeSet<string, string>> itemsStream = sourceCache.Connect();

        IObservable<IChangeSet<string, string>> updateStream = itemsStream.TransformWithInlineUpdate(
            x => x,
            (item, update) => { }
        );

        ITestableObserver<IChangeSet<string, string>> observerCache = testScheduler.CreateObserver<IChangeSet<string, string>>();
        ITestableObserver<IChangeSet<string, string>> observerUpdate = testScheduler.CreateObserver<IChangeSet<string, string>>();

        using IDisposable subscriptionCache = itemsStream.Subscribe(observerCache);
        using IDisposable subscriptionUpdate = updateStream.Subscribe(observerUpdate);

        sourceCache.AddOrUpdate("1");
        sourceCache.AddOrUpdate("1");

        //First add then update, that's right
        Assert.Equal(
            [ChangeReason.Add, ChangeReason.Update],
            observerCache.Messages.SelectMany(message => message.Value.Value.Select(changes => changes.Reason)).ToArray()
        );

        // The test will fail; it returns ChangeReason.Refresh instead of ChangeReason.Update for the second element
        Assert.Equal(
            [ChangeReason.Add, ChangeReason.Refresh],
            observerUpdate.Messages.SelectMany(message => message.Value.Value.Select(changes => changes.Reason)).ToArray()
        );
    }
}

Expected behavior

An update should be sent as an update

Additional info

Seems like the problem is here