[18.0][MIG] base_tier_validation_definition_server_action: Migration to 18.0

[chaule97]

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[wlin-kencove]

While I can test the basic functionality of adding a tier validation server action I cannot actually run the validation since no models are currently enabled to to run with tier validation.

I think we need additional dependencies in order to test comprehensively. (see example for sale orders workflow above)

[github-actions[bot]]

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