deleteItem method
Implementation
void deleteItem(int index) {
if (_pagingState is PagingStateData<PageKeyType, ItemType>) {
final value = _pagingState as PagingStateData<PageKeyType, ItemType>;
var items = [...value.items];
items.removeWhere((element) => items.indexOf(element) == index);
emit(PagingStateData(items, value.status, value.hasRequestNextPage));
}
}