MAGETWO-49985: product custom options export in reverse order fixed

[umarch06]

Description

Changed the sort order from descending to ascending while getting custom options for a product, currently default sort order (descending) was used while generating rows for custom options for a product, so now after importing custom options will be displayed in the same order as in which these were exported.

Manual testing scenarios

1. Create a simple product with two options, the 1st option is a dropdown and the 2nd option is a field, Save it.
2. System -> Export
3. System -> Import same file in same store or other
4. After import, in UI, product options will be in the same order as in it was exported.

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

[dmanners]

According to the technical guidelines method chaining should be avoided (http://devdocs.magento.com/guides/v2.2/coding-standards/technical-guidelines.html#2-class-design in 2.15). Would you be able to update this part of the code base to not use chaining. Something like

$options->reset();
$options->addOrder('sort_order', 'ASC');
$options->addTitleToResult($storeId);
$options->addPriceToResult($storeId);
$options->addProductToFilter($productIds);
$options->addValuesToResult($storeId);

This should have the same results but avoids the method chaining.

Of course please also check that this still works as expected after your changes.