fix(GlListbox): Allows listbox to accept null values as defaults

mentioned in commit 515d9718

mentioned in merge request gitlab-svgs!1140 (merged)

mentioned in merge request gitlab-org/frontend/pajamas-adoption-scanner!367 (merged)

mentioned in merge request gitlab!188388 (merged)

mentioned in merge request gitlab-org/gitlab-services/design.gitlab.com!4385 (merged)

mentioned in merge request gitlab-svgs!1145 (merged)

mentioned in merge request status-page!903

mentioned in merge request gitlab!188883 (merged)

mentioned in merge request gitlab-org/gitlab-services/design.gitlab.com!4394 (merged)

mentioned in merge request gitlab-org/frontend/playground/accessibility-scanner!70 (merged)

mentioned in merge request gitlab-org/frontend/pajamas-adoption-scanner!370 (merged)

mentioned in merge request gitlab-org/frontend/playground/accessibility-scanner!71 (merged)

mentioned in merge request gitlab-org/frontend/pajamas-adoption-scanner!372 (closed)

mentioned in merge request gitlab-org/editor-extensions/gitlab-jetbrains-plugin!1680 (merged)

mentioned in merge request gitlab-org/technical-writing/docs-gitlab-com!682 (closed)

mentioned in merge request gitlab-org/technical-writing/docs-gitlab-com!683 (merged)

mentioned in merge request gitlab-org/editor-extensions/gitlab-jetbrains-plugin!1731 (merged)