Even if a many2many field is forcely set to be sortable, it should not be included in the list of custom groupby options if it's an un-stored field. closes odoo/odoo#104978 X-original-commit: 9ba52387481bb0720c5d4f5d8a86c3ad6e801137 Signed-off-by: Mathieu Duckerts-Antoine <dam@odoo.com> Signed-off-by: Joseph Caburnay (jcb) <jcb@odoo.com>