columnviewtitle: Prevent header clicks from propagating

columnviewtitle: Prevent header clicks from propagating

The header in GtkColumnView has multiple event handlers
there is a ::pressed handler in GtkColumnView for
resizing the columns in CAPTURE as well as a motion
and drag controller.  The ::release handler is in
GtkColumnViewTitle.   We can't claim the event in the
existing handlers because then the ::release handler will
never get called.  Currently, however, all clicks get propagated
to the ColumnView from the header which can be problematic.
Since we don't usually want the clicks from the header
handled on the view, claim it in the BUBBLE phase.

Fixes: https://gitlab.gnome.org/GNOME/gtk/-/issues/5425