Add BufferIO for FileResponse

As a performance on staging server is bad - need try to use BufferIO for FileResponse

esi/scraper/views.py

+import io
 from datetime import datetime, time
 from django.shortcuts import render, HttpResponseRedirect, reverse, HttpResponse
-from django.http import JsonResponse
+from django.http import JsonResponse, FileResponse
 from django.views.generic import ListView, CreateView, UpdateView
 from django.contrib.auth.decorators import login_required
 from django.utils.decorators import method_decorator
@@ -54,8 +55,9 @@ class JobListView(ListView):
         if action == 'restart':
             return JsonResponse(self.service.restart_job(job_id))
         if action == 'log':
-            log = self.service.get_log(job_id)
-            return HttpResponse(log, content_type='text/plain')
+            log = io.BytesIO(self.service.get_log(job_id))
+            # return HttpResponse(log, content_type='text/plain')
+            return FileResponse(log)
 
 
 @method_decorator(login_required, name='dispatch')