[2.2] Add support for validation message callback

[floorz]

Original pull request: #20079

Description (*)

• Adds a type check for message just before attempting to process validation params on it
• Resolves the callback if it was one using the validation rule for the 'this' context

Fixed Issues (if relevant)

1. Magento Ui form validator message callback not supported #20078: Magento Ui form validator message callback not supported

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

Hi @orlangur, thank you for the review.
ENGCOM-4672 has been created to process this Pull Request

[soleksii]

✔️ QA Passed

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After:

[m2-assistant]

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