[FIX] expression: use of `child_of` with `many2many`

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A crash occurs.

This is because of an incorrect SQL:

`WHERE "category_id" IN ()`

In case of an empty list `ids2`, we fall back on `(None,)`

Note that it appears only in v13 because `child_of` was added at [1],
but the issue also exists in v12.

[1] https://github.com/odoo/odoo/blob/b6325ae45b830a725f6ab6706b70f65c809be4a7/odoo/addons/base/views/res_partner_views.xml#L471



opw-2151129

closes odoo/odoo#41451

Signed-off-by: Nicolas Martinelli (nim) <nim@odoo.com>

odoo/osv/expression.py

@@ -1011,7 +1011,7 @@ class expression(object):
                         push(create_substitution_leaf(leaf, ('id', 'in', ids2), model))
                     else:
                         subquery = 'SELECT "%s" FROM "%s" WHERE "%s" IN %%s' % (rel_id1, rel_table, rel_id2)
-                        push(create_substitution_leaf(leaf, ('id', 'inselect', (subquery, [tuple(ids2)])), internal=True))
+                        push(create_substitution_leaf(leaf, ('id', 'inselect', (subquery, [tuple(ids2) or (None,)])), internal=True))
 
                 elif right is not False:
                     # determine ids2 in comodel