RelatedManager.set() doesn't pass bulk keyword argument to clear()

[Jeremy Lainé]

For reverse many-to-one relations, the set method's bulk keyword argument is passed down to the add() and remove() methods. It isn't however passed down to the clear() method:

​https://github.com/django/django/blob/265506bbc347a6b3fcc6c66ab1a2417b3b7ea57a/django/db/models/fields/related_descriptors.py#L711

This looks like a bug, as passing bulk=False, clear=True results in the following behavior:

• clear() is invoked in "bulk" mode, not triggering signals
• add() is invoked in "non-bulk" mode, signals are triggered

Admitedly, I'm not too sure why you would want to do this, but at the very least the docs should mention if this combination is unsupported.

I spotted this while reading the related_descriptors.py code to fix #29440.