Fix focus style gap at top in keyline-block
Fix focus style gap at top in keyline-block

File-list items contained by div.keyline-block's
are pushed down 3px more than elsewhere which
creates a gap between the top of the focus style
and the keyline above. This extends the part of
the focus style made up by a box-shadow by 3px so
it covers the gap.

alphagov/notifications-admin,alphagov/notifications-admin,alphagov/notifications-admin,alphagov/notifications-admin