fix(GlAnimatedIcon): Apply design suggestions

mentioned in commit ab84799f

mentioned in merge request gitlab!166177 (merged)

mentioned in merge request gitlab-org/editor-extensions/gitlab-jetbrains-plugin!984 (merged)

mentioned in merge request status-page!903

mentioned in merge request gitlab!166415 (closed)

mentioned in merge request gitlab!166460 (closed)

mentioned in merge request gitlab-org/gitlab-services/design.gitlab.com!4049 (closed)

mentioned in merge request gitlab-org/gitlab-services/design.gitlab.com!4067 (closed)

mentioned in merge request gitlab-org/frontend/pajamas-adoption-scanner!349 (merged)

mentioned in merge request gitlab-org/frontend/playground/accessibility-scanner!51 (merged)