Introduce aria-disabled pattern to disclosure dropdown items

See merge request !6216

Merged-by: Chad Lavimoniere <clavimoniere@gitlab.com>
Approved-by: Trevor Pierce <tpierce@gitlab.com>
Approved-by: Chad Lavimoniere <clavimoniere@gitlab.com>
Co-authored-by: Joseph Snyder <joe.snyder@kitware.com>

Resolve "Add Illustration: Sessions Empty State"

See merge request !6385

Merged-by: Jeremy Elder <jelder@gitlab.com>
Approved-by: Emily Bauman <ebauman@gitlab.com>
Approved-by: Scott de Jonge <sdejonge@gitlab.com>
Reviewed-by: GitLab Duo <gitlab-duo@gitlab.com>

GlAlert condense spacing

See merge request !6347

Merged-by: Thomas Hutterer <thutterer@gitlab.com>
Approved-by: Jeremy Elder <jelder@gitlab.com>
Approved-by: Thomas Hutterer <thutterer@gitlab.com>
Reviewed-by: Thomas Hutterer <thutterer@gitlab.com>
Reviewed-by: Scott de Jonge <sdejonge@gitlab.com>
Co-authored-by: Scott de Jonge <sdejonge@gitlab.com>
Co-authored-by: GitLab Bot <gitlab-bot@gitlab.com>