Further refinements
requested to merge issue/eu_cookie_compliance-3298345:3298345-withdraw-banner-keyboard-focus-2 into 8.x-1.x
- When withdraw banner is created (and not yet visible) ensure all focusable controls inside have tabindex -1
- Fixes an issue where the eu-cookie-compliance-popup-open body class is not removed and controls inside the banner remain focusable when cookies are declined and the pop-up closes.