Fix incorrect width on empty tables
Fix incorrect width on empty tables

Empty tables shouldn’t have `table-display: fixed` because it stops them
filling the width of their container.

gov-cjwaszczuk/notifications-admin,gov-cjwaszczuk/notifications-admin,gov-cjwaszczuk/notifications-admin,alphagov/notifications-admin,alphagov/notifications-admin,alphagov/notifications-admin,gov-cjwaszczuk/notifications-admin,alphagov/notifications-admin