Add database transaction handling

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

mayan/apps/linking/views.py

@@ -4,6 +4,7 @@ import logging
 
 from django.contrib import messages
 from django.core.exceptions import PermissionDenied
+from django.db import transaction
 from django.shortcuts import get_object_or_404
 from django.template import RequestContext
 from django.urls import reverse, reverse_lazy
@@ -47,6 +48,7 @@ class DocumentTypeSmartLinksView(AddRemoveView):
     related_field = 'smart_links'
 
     def action_add(self, queryset, _user):
+        with transaction.atomic():
             event_document_type_edited.commit(
                 actor=_user, target=self.main_object
             )
@@ -57,6 +59,7 @@ class DocumentTypeSmartLinksView(AddRemoveView):
                 )
 
     def action_remove(self, queryset, _user):
+        with transaction.atomic():
             event_document_type_edited.commit(
                 actor=_user, target=self.main_object
             )