[FIX] web: prevent search dropdowns to close on click inside

In the Filters, Group By and Favorites dropdowns,
when clicking outside the `li` elements but still
inside the dropdown menu itself
(like on the dividers,
or next to the advanced search `Apply` button),
the dropdowns was closed.

This behavior was annoying when doing an advanced search
with a field using the datetime picker, as, to close the datetime
picker, you have to click outside it, and when you did, it closed
automatically the filter dropdown... So you had to open it again to
finally apply the filter.

opw-674310