perf(SafeHtml): Add unbind hook to the directive

mentioned in commit 8886e0e7

mentioned in merge request status-page!893 (merged)

mentioned in merge request gitlab!142582 (closed)

mentioned in merge request gitlab!142686 (merged)

mentioned in merge request gitlab-docs!4555 (merged)

mentioned in merge request gitlab-org/gitlab-services/design.gitlab.com!3713 (merged)

mentioned in merge request gitlab!143271 (merged)

mentioned in merge request gitlab!143284 (closed)

mentioned in merge request gitlab-org/frontend/pajamas-adoption-scanner!268 (merged)

mentioned in merge request gitlab-org/frontend/pajamas-adoption-scanner!269 (merged)

mentioned in merge request gitlab-org/frontend/playground/accessibility-scanner!21 (merged)