Button | Twig | Add missing 'target' attribute

[danielamorse]

Jira

http://vjira2:8080/browse/BDS-1415

Summary

Added target to Twig-rendered button-style link if passed in via attributes.

Details

Currently the way to add a target to a button is to pass it in via Twig attributes. This adds the prop to the custom element but not the inner semantic <a>, so you have to wait until the JS kicks in for it to be added. This PR adds it to the Twig-rendered markup so that it works with and without JS.

Note: the button schema needs to be updated to include url and target. This will be handled in a separate ticket.

How to test

• Run the fix/button-missing-target branch locally.
• Add this code to any button demo page:

{% include "@bolt-components-button/button.twig" with {
  text: "This is a button",
  url: "http://pega.com",
  attributes: {
    target: "_blank"
  }
} only %}

• View the page with JS off and verify the link opens in a new window.

[sghoweri]

Shipit!