[WEB-2631] chore: changed the cascading logic for soft delete (#5829)

* chore: changed the cascading logic for soft delete

* chore: changed the delete key

* chore: added the key on delete in project base model

apiserver/plane/app/views/workspace/draft.py

@@ -279,7 +279,7 @@ class WorkspaceDraftIssueViewSet(BaseViewSet):
                         {
                             "updated_cycle_issues": None,
                             "created_cycle_issues": serializers.serialize(
-                                "json", created_records
+                                "json", [created_records]
                             ),
                         }
                     ),

apiserver/plane/bgtasks/deletion_task.py

@@ -21,8 +21,8 @@ def soft_delete_related_objects(
             try:
                 # Check if the field has CASCADE on delete
                 if (
-                    hasattr(field.remote_field, "on_delete")
-                    and field.remote_field.on_delete == models.CASCADE
+                    not hasattr(field.remote_field, "on_delete")
+                    or field.remote_field.on_delete == models.CASCADE
                 ):
                     if field.one_to_many:
                         related_objects = getattr(instance, field.name).all()

apiserver/plane/db/models/project.py

@@ -181,7 +181,7 @@ class ProjectBaseModel(BaseModel):
         Project, on_delete=models.CASCADE, related_name="project_%(class)s"
     )
     workspace = models.ForeignKey(
-        "db.Workspace", models.CASCADE, related_name="workspace_%(class)s"
+        "db.Workspace", on_delete=models.CASCADE, related_name="workspace_%(class)s"
     )
 
     class Meta: