🐛 Fix: [#32] portfolio 이전 대표 내리기 save() 추가

portfolios/views.py

@@ -56,6 +56,7 @@ class PortfolioSetRepresentAPIView(APIView):
             return Response({"message": "Not owner"}, status=status.HTTP_403_FORBIDDEN)
         if before_represent := Portfolio.objects.filter(owner=user, is_represent=True).first():
             before_represent.is_represent = False
+            before_represent.save()
         portfolio.is_represent = True
         portfolio.save()
         return Response({"message": "change represent success"}, status=status.HTTP_200_OK)