Fix static analysis violations with cursor pagination

[tolry]

When using cursor pagination, access to has_more and cursor are labelled as violations by phpstan or psalm, since those properties are protected on AbstractModel although they are readable publicly via __get()

sample code

$cursor = null;
do {
    $filter = ["customer_uuid" => $uuid];
    if ($cursor) {
        $filter["cursor"] = $cursor;
    }

    $collection = \ChartMogul\CustomerInvoices::all($filter);

    foreach ($collection->invoices as $invoice) {
        // do something
    }

    $cursor = $collection->cursor;
} while ($collection->has_more);

[swember]

Hello @tolry, thanks a lot for the contribution. Could you please provide which settings for phpstan you use. I tried to create a new project and use your code in it and I haven't got any complaints from phpstan.