fix: add scrollend event type

[arslanastral]

Added scrollend event type which is useful when you want to fire an event handler after scrolling has finished vs firing continuously while scrolling as scroll does. closes #10258

Ref:
https://developer.mozilla.org/en-US/docs/Web/API/Document/scrollend_event
https://developer.chrome.com/blog/scrollend-a-new-javascript-event
https://caniuse.com/?search=scrollend

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