WikimediaUI theme: Fix visual regression on toolbar menu border
WikimediaUI theme: Fix visual regression on toolbar menu border

Fixing regression introduced in Ifcdb27ff59f2169177be516cef78ecac83bd2c69
Toolbar menus need to apply toolbar's `border-color`, not ToolGroups.

Change-Id: I404a9773a0311b5841fee3e3df63d2ec6b8d69e3

wikimedia/oojs-ui,wikimedia/oojs-ui,wikimedia/oojs-ui,wikimedia/oojs-ui