[FIX] web : indeterministic crash in Many2ManyTagsField tests

The goal of this commit is to fix indeterministic crashes
in Many2ManyTagsField test suite.

We could see that the wrong helper was used in some tests. We used
selectDropdownItem after an editInput on this same field.

Cause of the error:
editInput => event input debounce which causes the autocomplete to open.
selectDropdownItem => event click which causes the autocomplete to open.
                     After this event, a second click takes place to
                     select the dropdown item (call to clickOpenedDropdownItem).

The setTimeout is not patched, it is possible that the input event takes
place after the click which does not cause any crash. But if the click
event happens after the input then the autocomplete is closed before
the dropdown item is selected.

To solve this, we will patch the setTimeout and we will use only
clickOpenedDropdownItem to select the dropdownItem.

We also patched the setTimout in all tests to avoid indeterminate
behavior related to the debounce in the autocomplete input.

closes odoo/odoo#105564

Signed-off-by: Aaron Bohy (aab) <aab@odoo.com>