This patch ports KJots from deprecated KBookmarksMenu API (see D25660: Decouple KBookmarksMenu from KActionCollection).
On my machine, it also fixes a crash (bm_action was null for some reason,
I did not investigate it though).
It also fixes the shortcuts collision (action->setShortcut was not enough,
one also needs to run actionCollection->setDefaultShortcut).
BUG: 384000