[FIX] web: kanban: keep column folded when d&d a record

In a grouped kanban view, drag a record and drop it in a folded
column. Before this commit, it opened and loaded the target column.
It shouldn't, the column should remain folded. This behavior has
been introduced in v16 with the wowl views.

This commit restores the legacy kanban behavior, which keeps the
target column folded and thus doesn't load it. We ensure that
the progressbar of the source column is correctly updated though.

Task 3208098

closes odoo/odoo#115628

Signed-off-by: Géry Debongnie <ged@odoo.com>