popovers: Avoid focus outline on \vdots when actions popover is open.
popovers: Avoid focus outline on \vdots when actions popover is open.

Now that we show the \vdots icon while the actions popover is open,
there's a weird looking behavior where a focus outline appears around
the \vdots icon, only if you clicked on the icon itself, not its
square containing click arrow.

Disable this unintended behavior, which disrupts the otherwise
simulated state where focus is in the popover (but no row is focused).

zulip/zulip,zulip/zulip,zulip/zulip,zulip/zulip,zulip/zulip,zulip/zulip,zulip/zulip