[Backport] Adjust table for grouped products

[mage2pratik]

Original Pull Request

#20808

I think there is a mistake here in declaring a tbody tag for every iteration ?

Description (*)

Fixed Issues (if relevant)

1. magento/magento2#<issue_number>: Issue title
2. ...

Manual testing scenarios (*)

1. ...
2. ...

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 @mage2pratik. Thank you for your contribution
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[magento-engcom-team]

Hi @sidolov, thank you for the review.
ENGCOM-4233 has been created to process this Pull Request

[ghost]

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