fix edit button for some panels

fix edit button for some panels

when using the 'run_editor' function provided by the ObjectGrid,
we have to make sure the function runs in the context of the grid,
not in that of the button, else we cannot access the
selectionModel/rows/etc. of the grid

this happened with the switch to the widget toolkit

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
Reviewed-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Tested-by: Thomas Lamprecht <t.lamprecht@proxmox.com>