Custom Batching notifications templates are not persisted after a Jira restart

Issue Summary

Custom Batching notifications templates are not persisted after a Jira restart

Steps to Reproduce

1. Follow the steps from Customizing email content in Jira Server to modify one of the batched notifications templates
2. Trigger one notification to confirm the changes were applied to the notification template
3. Restart Jira
4. Trigger another batched notification

Expected Results

The changes that were applied to the batching notifications template should be persisted after a Jira restart.

Actual Results

As soon we restart Jira, the batching notifications templates are set back to the default template.

Workaround

Upload the customized templates per Customizing email content in Jira Server after a Jira restart.