[IMP]pms: ref param in folio method do_refund

pms/models/pms_folio.py

@@ -2000,6 +2000,7 @@ class PmsFolio(models.Model):
         partner=False,
         date=False,
         pay_type=False,
+        ref=False,
     ):
         """
         create folio refund
@@ -2011,6 +2012,8 @@ class PmsFolio(models.Model):
         reference = folio.name
         if folio.external_reference:
             reference += " - " + folio.external_reference
+        if ref:
+            reference += ": " + ref
         vals = {
             "journal_id": journal.id,
             "partner_id": partner.id,