Add a more accurate missing notifications message

Notifications could be missing because:
- none have been created yet
- they’ve been deleted

This commit adds separate error messages for each case, rather than a
less helpful generic one.

app/main/views/jobs.py

@@ -480,6 +480,7 @@ def get_job_partials(job, template):
             job=job,
             template=template,
             template_version=job['template_version'],
+            service_data_retention_days=service_data_retention_days,
         ),
         'status': render_template(
             'partials/jobs/status.html',