[Forwardport] Update time12h javascript validation rule to be compatible with js minify

[dmytro-ch]

Original PR: #17652

Update time12h javascript validation rule to be compatible with js minify

Description

The space in the validation rule causes this rule to not work correctly when js minify is enabled, as it strips the space out of the validation rule regex.

Fixed Issues (if relevant)

1. UI validation rule for valid time am/pm doesn't work when js is minified #17648: UI validation rule for valid time am/pm doesn't work when js is minified

Manual testing scenarios

1. Validation rule with space doesn't work if js minify is enabled

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

Hi @sidolov, thank you for the review.
ENGCOM-2824 has been created to process this Pull Request

[magento-engcom-team]

Hi @dmytro-ch. 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.