Upgrade django-postgres-extra to 1.21a8

Photonios · Photonios · commit 04f15363bb35 · 2018-04-01T18:28:43.000+03:00
diff --git a/requirements/base.txt b/requirements/base.txt
@@ -1 +1 @@
-django-postgres-extra==1.21a7
+django-postgres-extra==1.21a8
