API for disabling default validators for Binder

[vursen]

Describe your motivation

Binder currently doesn't provide a way to opt-out of the default validator feature.

In the case of Flow components, the default validator checks component constraints. However, there are situations where the developer would prefer to define constraints on the component for their visual aspects but handle the actual validation manually using a custom validator.

Describe the solution you'd like

A method to disable getDefaultValidator when binding a field to a Binder.

Describe alternatives you've considered

Flow components don't seem to be a good place for such a public method since the API specifically targets Binder.

Additional context

Related to vaadin/platform#3066 and vaadin/flow-components#3406 (comment)

[vursen]

There has been a discussion about the API in https://github.com/orgs/vaadin/discussions/4664

[vursen]

Note, the JavaDoc needs to be updated to describe what the default validator is and how it can be disabled using this API.

[mshabarov]

Planned for next sprint in Vaadin Flow team.