IBX-10375 - Fix validator names being mangled in production builds

[ryanolee]

N.b there is no v5 stable branch so opening this into main

🎫 Issue	IBX-10375

What

This PR intruduces a new method to eZ validators called "getValidatorName" which returns a reliable stable refernce to the name of the given validator. This PR also updates to references where the validator names are pulled.

Why

In production mode only references to the validator.constructor.name are mangled into random letters.

In eZ 3.3 decisions about what errors to show in the page builder are predicated on the field-set these validator names rely on.

How

By moving to a hard coded string the minified JS does not effect the names of validators as given.

[sonarqubecloud]

Quality Gate failed

Failed conditions
13.0% Duplication on New Code (required ≤ 3%)

See analysis details on SonarQube Cloud

[dew326]

Thanks for the contribution @ryanolee.
The PR overall looks good. We would need this to be created and targeted to branch 4.6 so we can include this fix as a part of 4.6.x.

[ryanolee]

Thanks @dew326 - recreated in 4.6 here https://github.com/ibexa/admin-ui/pull/1703/files