Added verification for new claim - step 1

@whoojemaflip Can you please have a look at this for me?

@jairodiaz [this file](https://github.com/ministryofjustice/civil-claims-spec/blob/1cd1555a4651cfaa863dc4e161acf13e6924b58e/support/step_definitions/01_Start_a_case/01_Personal_details_steps.rb) will be relevant for the validations on **/claims/new** page.

Thanks