[iOS] Review possible memory leak with CollectionViewHandler2.SubscribeToItemsLayoutPropertyChanged

[PureWeen]

Description

Reviewing some memory dumps and it seems like there's a possible leak with CollectionViewHandler2

maui/src/Controls/src/Core/Handlers/Items2/CollectionViewHandler2.iOS.cs

Lines 202 to 220 in 5fc2590

	void SubscribeToItemsLayoutPropertyChanged(IItemsLayout itemsLayout)
	{
	if (itemsLayout is not null)
	{
	itemsLayout.PropertyChanged += (sender, args) =>
	{
	if (args.PropertyName == nameof(ItemsLayout.SnapPointsAlignment) ||
	args.PropertyName == nameof(ItemsLayout.SnapPointsType) ||
	args.PropertyName == nameof(GridItemsLayout.VerticalItemSpacing) ||
	args.PropertyName == nameof(GridItemsLayout.HorizontalItemSpacing) ||
	args.PropertyName == nameof(GridItemsLayout.Span) ||
	args.PropertyName == nameof(LinearItemsLayout.ItemSpacing))
	{
	UpdateLayout();
	}
	};
	}
	}

I'm not sure off hand the most reasonable place to unsubscribe from this.
We could/should do it in disconnecthandler but it'd be nice to do it somewhere else that we always know it'll fire from.

Maybe we can unsubscribe/subscribe to this when the view is attached/removed from the window?

Maybe there's a way to subscribe to it from the level of the CollectionView itself and we have it fire a mapper that triggers the UpdateLayout call?

I'm a little curious why we're subscribing to events on a static variable, that feels like it won't do anything useful.

Workaround

This issue comes from the default ItemsLayout because a static instance which means if you subscribe to it you won't get GC'd

<CollectionView>
                <CollectionView.ItemsLayout>
                    <LinearItemsLayout Orientation="Vertical" />
                </CollectionView.ItemsLayout>
            </CollectionView>