Revert "Merge branch 'notes_widget_create_note_mutation' into 'master'"

Purpose of Revert

gitlab-org/quality/engineering-productivity/master-broken-incidents#491 (closed)

closes #386679 (closed)

Check-list

• Create an issue to reinstate the merge request and assign it to the author of the reverted merge request.
• If the revert is to resolve a 'broken master' incident, please read through the Responsibilities of the Broken 'Master' resolution DRI
• Add the appropriate labels before the MR is created (we can only skip CI/CD jobs if the labels are added before the CI/CD pipeline gets created)