Editing diff notes doesn't work

Summary

Once a new comment is added to a diff in an MR, editing the comment is not possible without reloading the page.

Steps to reproduce

• Open any MR
• Go to changes tab
• Add a comment to any line from the diff
• Once comment is created, try to edit it

What is the current bug behavior?

Edit form appears broken when Edit button is clicked on an already created note.

What is the expected correct behavior?

User should be able to see Edit form when clicked on edit on a diff comment.

Screenshots (GIF)