fix(GlCarousel): Change focus border size

mentioned in commit ed3bd08a

mentioned in merge request gitlab-org/frontend/pajamas-adoption-scanner!181 (closed)

mentioned in merge request status-page!843 (merged)

mentioned in merge request gitlab-org/frontend/pajamas-adoption-scanner!182 (merged)

mentioned in merge request status-page!844 (merged)

mentioned in merge request gitlab!128113 (closed)

mentioned in merge request gitlab-org/gitlab-services/design.gitlab.com!3432 (merged)

mentioned in merge request gitlab-docs!4143 (merged)

mentioned in merge request gitlab-org/gitlab-services/design.gitlab.com!3479 (merged)

mentioned in merge request gitlab-docs!4145 (merged)

mentioned in merge request gitlab!126562 (merged)