Add streaming audit events for notes

What does this MR do and why?

Trigger streaming audit events when a note is created, updated, and deleted

References

Related to #3706 (closed)

How to set up and validate locally

1. Go to "Secure > Audit events" then open the "Streams" tab.
2. Create an HTTP streaming destination. You can use a URL from https://requestcatcher.com/ or other similar tools to easily see the streamed events.
3. Create, update, or delete notes

MR acceptance checklist

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