The duplication of a task crashes at the following:
`content = myPad.getHtml(path).get('html', '')`
The copy mechanism is quite cumbersome:
- In `copy` method, generate an URL of a pad which doesn't exist since
`object_id` is still undefined.
- The `create` method somehow attempts to fill in the previously created
pad thanks to `_set_pad_value`.
The logic is made simpler. The pad URL field is set as `copy=False`,
therefore the create mechanism will take care of handling the pad
creation and its synchronization.
opw-1818757