[Forwardport] Fix of invalid price for integer currencies when amount less than group size

[vkublytskyi]

Description

After correct fixes in #15540 client-side formatting starts corrupt prices in currencies without minor units if price amount is less then number group size (usually equal to 3 numbers).

Fixed Issues (if relevant)

1. Wrong price amount on product page #11717: Wrong price amount on a product page

Manual testing scenarios

STR:

1. Install Magento
2. Set USD as a base currency
3. Set JPY as display currency (it also should be enabled as available currency)
4. Add product with price 0.01 USD
5. Add currency rate as 110 JPY for 1 USD
6. Open product page

AC: price 0,001 is displayed (wrongly added 0 to have group separator visible)

ER: price 1 is displayed (no decimal part, no preceding 0)

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)

[magento-cicd2]

All committers have signed the CLA.

[magento-engcom-team]

Hi @vkublytskyi. Thank you for your contribution
Here is some useful tips how you can test your changes using Magento test environment.
Add the comment under your pull request to deploy test or vanilla Magento instance:

• @magento-engcom-team give me test instance - deploy test instance based on PR changes
• @magento-engcom-team give me {$VERSION} instance - deploy vanilla Magento instance

For more details, please, review the Magento Contributor Assistant documentation

[magento-engcom-team]

Hi @orlangur, thank you for the review.
ENGCOM-2212 has been created to process this Pull Request

[magento-engcom-team]

Hi @vkublytskyi. Thank you for your contribution.
We will aim to release these changes as part of 2.3.0.
Please check the release notes for final confirmation.