Fix git repo links on /healthz-cron/ page (#7412)

Fix #7411

bedrock/utils/git.py

@@ -9,6 +9,7 @@ from subprocess import check_output, CalledProcessError, STDOUT
 from io import StringIO
 
 from django.conf import settings
+from django.utils.encoding import force_str
 
 import timeago
 from pathlib2 import Path
@@ -38,7 +39,7 @@ class GitRepo:
         finally:
             os.chdir(curdir)
 
-        return output.strip()
+        return force_str(output.strip())
 
     @property
     def current_hash(self):

bedrock/utils/migrations/0003_auto_20190710_1159.py

@@ -0,0 +1,24 @@
+# Generated by Django 2.2.3 on 2019-07-10 18:59
+
+from django.db import migrations
+
+
+def fix_bytes_repr(apps, schema_editor):
+    """Values were stored as strings with the "b''" in them. This should fix that."""
+    GitRepoState = apps.get_model('utils', 'GitRepoState')
+    for repo in GitRepoState.objects.all():
+        if repo.latest_ref.startswith("b'"):
+            # strip the b' off the start and the ' off the end
+            repo.latest_ref = repo.latest_ref[2:][:-1]
+            repo.save()
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('utils', '0002_auto_20180522_1249'),
+    ]
+
+    operations = [
+        migrations.RunPython(fix_bytes_repr)
+    ]