Add migration to delete an X509 cert for hinj user

gracedb/ligoauth/migrations/0015_delete_hinj_cert.py

+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.16 on 2018-12-11 18:21
+from __future__ import unicode_literals
+
+from django.db import migrations
+
+ACCOUNT_NAME = 'hinj'
+CERT_SUBJECT = '/DC=org/DC=ligo/O=LIGO/OU=Services/CN=hinj/ldas-grid.ligo.caltech.edu'
+
+
+def delete_cert(apps, schema_editor):
+    X509Cert = apps.get_model('ligoauth', 'X509Cert')
+
+    # Get cert and delete
+    cert = X509Cert.objects.get(subject=CERT_SUBJECT)
+    cert.delete()
+
+
+def create_cert(apps, schema_editor):
+    User = apps.get_model('auth', 'User')
+
+    # Get user and create certificate
+    user = User.objects.get(username=ACCOUNT_NAME)
+    user.x509cert_set.create(subject=CERT_SUBJECT)
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('ligoauth', '0014_add_new_dashboard_cert'),
+    ]
+
+    operations = [
+        migrations.RunPython(delete_cert, create_cert),
+    ]