Chuck Norris jokes step inputs

bitirise.yml

inputs:
  - category:
    opts:
      title: "Joke category, optional."
      summary: |
        Optional category of the joke, see [list of available categories](https://api.chucknorris.io/jokes/categories).
        If empty joke won't be restricted to any category.
      is_expand: true
      is_required: false
  - api_base_url: "https://api.chucknorris.io"
    opts:
      title: "API base URL"
      summary: |
        Base URL of the API. Defaults to _https://api.chucknorris.io_. See
        [chuck-api](https://github.com/chucknorris-io/chuck-api) for more info about running your own backend.
      is_expand: true
      is_required: true