When clicking on the trash to remove a line (e.g. a sale order line
in a quotation form view) while editing another line, it produces a
traceback (in most cases), or behaves randomly (less frequently)
like removing both lines, or one of them, or maybe none of them.
Anyway, this feature doesn't work at all, so this commit simply disables
it when we are in edition mode.
In a perfect world, we would fix the feature instead of disabling it,
but the code of the list editable is so instable that it would most
certainly break something else.
Closes#13778
Aaron Bohy
1f06cc4168