fix: resolve #1642 Notification Hub demo cancelling messages after on…

[codynova]

Fix #1642

Why

The Notification Hub useTransition example persists notifications when clicking to "cancel" after onRest. In this scenario, the "cancel" function cancels the leave animation.

What

Ensure that "cancel" is not called during the leave animation by checking the value of the life prop when clicking the "x" button

Checklist

• Documentation updated
• Demo added
• Ready to be merged

[codesandbox-ci]

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Latest deployment of this branch, based on commit f6e1b2c:

Sandbox	Source
spring-card	Configuration
spring-goo-blobs	Configuration
spring-flip-card	Configuration
spring-slide	Configuration
spring-draggable-list	Configuration
spring-cards-stack	Configuration
spring-viewpager	Configuration
spring-simple-transition	Configuration
spring-image-fade	Configuration
spring-list-reordering	Configuration
spring-masonry	Configuration
spring-animating-auto	Configuration
spring-multistage-transition	Configuration
spring-chain	Configuration
spring-svg-filter	Configuration
spring-css-keyframes	Configuration
spring-tree	Configuration
spring-notification-hub	Configuration
initial-rocket	Configuration
spring-notification-hub	Configuration
spring-notification-hub	Configuration
spring-notification-hub	Issue #1642

[joshuaellis]

Thanks for the contribution! ⭐