Fix optimistic update of work item notes

What does this MR do and why?

This MR fixes an optimistic update of work item notes that was broken in !115222 (merged)

Screenshots or screen recordings

Before	After
before	after

How to set up and validate locally

1. Open a task
2. Add a few notes
3. Edit a note and save changes
4. You should see updated note instantly

MR acceptance checklist

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