code: @POST
    @Path("{id}/email/confirm")
    @PermitAll
    public Response confirmChangeEmail(@PathParam("id") Long userId, EmailRequest request) {
      checkNotNull(userId);
      checkNotNull(request.getToken());
  
      boolean isSuccess = userService.confirmEmailAddressChangeUsingToken(userId, request.getToken());
      return isSuccess ? Response.noContent().build() : Response.status(Response.Status.BAD_REQUEST).build();
    }
docs: User confirm changing email.
  The token is verified and the temporary stored email will not be permanently saved as the users email.
  
  @param userId unique email
  @return 204 if success