[Issue] Fixing the flaky test that fails because of the wrong formatted date value

[m2-assistant]

This issue is automatically created based on existing pull request: #31509: Fixing the flaky test that fails because of the wrong formatted date value

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Description (*)

This PR is supposed to fix the failing MFTF test, that fails because of the wrong formatted date value.

Failed testing for '01/4/21' in default_value_date's value: '1/4/21'
Failed asserting that an array contains '01/4/21'.

Related Pull Requests

Fixed Issues (if relevant)

1. Fixes magento/magento2#<issue_number>

Manual testing scenarios (*)

1. ...
2. ...

Questions or comments

Actually, the root issue is somewhere deeper, because the date input removes the 0 for days like 04/4/2021.

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 are green)

[eduard13]

Fixed in scope of 427f9bf.