[FIX] crm: keep order of lead ids when mass converting

Purpose of this commit is to avoid the use of sets in convert wizard. This set
is used to compute ids of leads to merge and to convert. Using a set make order
impossible to predict. Using lists allows to have reproducible tests notably.

Spotted when working on task ID-2086889

addons/crm/wizard/crm_lead_to_opportunity_mass.py

@@ -81,6 +81,8 @@ class Lead2OpportunityMassConvert(models.TransientModel):
     def action_mass_convert(self):
         self.ensure_one()
         if self.name == 'convert' and self.deduplicate:
+            # TDE CLEANME: still using active_ids from context
+            active_ids = self._context.get('active_ids', [])
             merged_lead_ids = set()
             remaining_lead_ids = set()
             for lead in self.lead_tomerge_ids:
@@ -94,10 +96,11 @@ class Lead2OpportunityMassConvert(models.TransientModel):
                         lead = duplicated_leads.merge_opportunity()
                         merged_lead_ids.update(duplicated_leads.ids)
                         remaining_lead_ids.add(lead.id)
-            active_ids = set(self._context.get('active_ids', {}))
-            active_ids = (active_ids - merged_lead_ids) | remaining_lead_ids
+            # rebuild list of lead IDS to convert, following given order
+            final_ids = [lead_id for lead_id in active_ids if lead_id not in merged_lead_ids]
+            final_ids += [lead_id for lead_id in remaining_lead_ids if lead_id not in final_ids]
 
-            self = self.with_context(active_ids=list(active_ids))  # only update active_ids when there are set
+            self = self.with_context(active_ids=final_ids)  # only update active_ids when there are set
         return self.action_apply()
 
     def _convert_handle_partner(self, lead, action, partner_id):