feat(ui5-button): make click button preventable

[nnaydenow]

Currently, the click event on the ui5-button is the native click event from the user interaction. This creates some problems. One main issue is that the click event cannot be prevented because the event handler in the template is always attached first. This means that the isPrevented flag is missing if the event is prevented during the bubble phase.

A bigger problem happens when the ui5-button has type="Submit" and is inside a HTML form element. In this case, each time the button is clicked, the form is submitted, even if the click event is prevented.

This pull request fixes the issue by changing the click event to a CustomEvent, instead of the native Event. This change is a soft breaking change because, in most cases, only event.target or event.currentTarget are used, and no other event details are usually needed. To provide backward compatibility the new custom event includes the original native event inside its e.detail.nativeEvent, so users can still access the original event if needed.

Fixes: #11103
Fixes: #9830