feat(banner): banner without title and no clickable

[christianpe98]

Motivation

From motive, our intention is to have banners that are not clickable and do not have a title. Right now, the X banner forces any banner to have a URL to redirect to and a title. In this PR we propose a solution to support X banners and the banners Motive needs.

Main changes

banner.model.ts

• url and title are optional.

banner.vue

• If the banner has a URL it will be clickable, triggering the appropriate events, otherwise it will just be an image(with or without title).
• If there is an error loading the banner image, the banner will be removed from the DOM.
• If the banner does not have a title, the alternative text of the image will be "Banner" and the heading(h2) will not be rendered.

banner.spec.ts

We have defined some unit tests at component level using Jest(x-components/src/x-modules/search/components/__tests__/banner.spec.ts) and others using Cypress(x-components/tests/unit/banner.spec.ts). We use Cypress to check that when loading an image, if an error occurs the banner is not rendered.

For the tests we have modified the existing banner factory, this has caused some changes in other tests(mocked-responses.spec.ts).