Tratamento de Erro não ocorre no Spring Boot

Boa tarde,

O erro não é tratado quando envio um JSON vazio.

<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-validation</artifactId>
</dependency>

package br.com.alura.forum.controller.config.validacao;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.MessageSource;
import org.springframework.context.i18n.LocaleContextHolder;
import org.springframework.http.HttpStatus;
import org.springframework.validation.FieldError;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseStatus;
import org.springframework.web.bind.annotation.RestControllerAdvice;

import java.util.ArrayList;
import java.util.List;

@RestControllerAdvice
public class ErroDeValidacaoHandler {

    @Autowired
    private MessageSource messageSource;

    @ResponseStatus(code = HttpStatus.BAD_REQUEST)
    @ExceptionHandler(MethodArgumentNotValidException.class)
    public List<ErroDeFormularioDto> handle(MethodArgumentNotValidException exception){

        List<ErroDeFormularioDto> dto = new ArrayList<>();
        List <FieldError> fieldErrors = (List<FieldError>) exception.getBindingResult().getFieldError();
        fieldErrors.forEach(e -> {
            String mensagem = messageSource.getMessage(e, LocaleContextHolder.getLocale());
            ErroDeFormularioDto erro = new ErroDeFormularioDto(e.getField(), mensagem);
            dto.add(erro);
        });
        return dto;
    }

}