fix(listbox): Allow use of reset button on single select

mentioned in commit 0ccd2f45

mentioned in merge request status-page!822 (merged)

mentioned in merge request gitlab-org/frontend/pajamas-adoption-scanner!155 (merged)

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

mentioned in merge request gitlab-docs!4040 (merged)

mentioned in merge request status-page!828 (merged)

mentioned in merge request gitlab-org/frontend/pajamas-adoption-scanner!168 (merged)

mentioned in merge request gitlab!126046 (merged)

mentioned in merge request gitlab-docs!4074 (merged)

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