Follow-up fix for extra (dashed) border in non-js claimlistview

e.g. when viewing a diff, which no longer loads all the js.

wikibase-toolbar-wrapper is present in non-js, so the border
is still present in non-js.

We instead need to provide another css class that is present only
when the js initializes the add toolbar. This class can be used to
apply the dashed top border when the add toolbar is present, which
is the situation where it makes sense to have the dashed border
to separate the toolbar visually from the last statement in the
claimlistview.

Bug: 73172
Change-Id: I61141d81576602c67747cb460e3bbfe60961a7e8
Merge "Follow-up fix for extra (dashed) border in non-js claimlistview"