Fix migration ordering issue

The task model rework has some migration ordering issues,
this fixes that and ensures action migrations don't
continue until other steps are done.

Change-Id: I3c3669a12e5d5d6b11fdf0e49b14894468287b6a

adjutant/actions/migrations/0003_auto_20190610_0205.py

@@ -11,6 +11,10 @@ class Migration(migrations.Migration):
         ("actions", "0002_action_auto_approve"),
     ]
 
+    run_before = [
+        ("api", "0005_auto_20190610_0209"),
+    ]
+
     operations = [
         migrations.AlterField(
             model_name="action",