fix(GlFormDate): Add missing export

mentioned in commit ccdb3252

mentioned in merge request gitlab-org/frontend/playground/accessibility-scanner!45 (merged)

mentioned in merge request gitlab-org/frontend/pajamas-adoption-scanner!338 (merged)

mentioned in merge request status-page!903

mentioned in merge request gitlab!161336 (merged)

mentioned in merge request gitlab-org/frontend/playground/accessibility-scanner!46 (closed)

mentioned in merge request gitlab!161469 (closed)

mentioned in merge request gitlab-org/frontend/playground/accessibility-scanner!47 (merged)

mentioned in merge request gitlab!161481 (merged)

mentioned in merge request gitlab-org/gitlab-services/design.gitlab.com!3986 (merged)

mentioned in merge request gitlab-org/editor-extensions/gitlab-jetbrains-plugin!783 (closed)

mentioned in merge request gitlab-org/editor-extensions/gitlab-jetbrains-plugin!811 (closed)

mentioned in merge request gitlab-org/editor-extensions/gitlab-jetbrains-plugin!828 (merged)

mentioned in merge request gitlab-org/editor-extensions/gitlab-jetbrains-plugin!829 (closed)