[Forwardport] Fix #13415 : Duplicated elements id

[julienanquetil]

Original Pull Request
#15585

Description

Fixed Issues (if relevant)

1. Duplicated elements id in checkout page #13415: Duplicated elements id in checkout page

Manual testing scenarios

1. Chrome didn't display error in console related to non unique ID

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-engcom-team]

Hi @julienanquetil

Unfortunately, we cannot accept Pull Requests from branches created in magento2 repository.
Please use your own fork as a base for this Pull Request.

Thank you.