Backend show form save success message after notification cancel operation

[soeren-eckel-adesso]

A brief description of the issue goes here.

When adding a Form Saving Notifiacation Handler and cancel operation the form is not saved, but the backend ui shows a form saved message.

Reproduction

If you're filing a bug, please describe how to reproduce it. Include as much
relevant information as possible, such as:

Bug summary

Form save action dont't show proper notifiaction user message.

Specifics

Umbraco.Cms: 10.4.1
Umbraco.Forms: 103.0
Browser: Edge

Steps to reproduce

• Create a form
• add add Form Saving Notifcation Handler

public class FormSavingNotificationHandler : INotificationHandler<FormSavingNotification>
{
    public void Handle(FormSavingNotification notification)
    {
        notification.CancelOperation(new EventMessage("Error", "Test Error"));
    }
}

• save form

Expected result

Form shows error message to user

Actual result

Form shows success message

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This item has been added to our backlog AB#33490

[AndyButland]

We'll fix this up so you get a red error bar in this case, with your message included. Will be part of the next round of patch releases.