Issue Summary

In Jira itself, the notification is not sent to watchers without permission (Currently, watchers remains though permissions are removed).
Slack for Jira Data Center should follow it.
However, it seems that Slack for Jira Data Center send personal notifications for watchers without permission, when issues get updated.

Steps to Reproduce

1. Install Slack for Jira Data Center (official)
2. Integrate Jira with Slack
3. Login Jira with an user and watch a issue.
4. Enable slack account and slack notification from profile
5. Login with an admin user and remove the above user from the permission of  'browse project' of the project.
6. To send notification, update the issue the watcher is watching 

Expected Results

The personal notification(Slack DM from bot) should not sent, since the user does not have permission.

Actual Results

The personal notification(Slack DM from bot) was sent to the user.

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available