Fix scroll to bottom aria label

[nickvergessen]

[Vue warn]: Property or method "scrollTobottomAriaLabel" is not defined on the instance but referenced during render. Make sure that this property is reactive, either in the data option, or for class-based components, by initializing the property. See: https://vuejs.org/v2/guide/reactivity.html#Declaring-Reactive-Properties.
[Vue warn]: Invalid prop: type check failed for prop "size". Expected Number with value 24, got String with value "24".