Revert "Move notes.scss to page_bundles from page_specific_bundles"

Purpose of revert

gitlab-com/gl-infra/production#17209 (closed)

Checklist

• Create an issue to reinstate the merge request and assign it to the author of the reverted merge request. #433424
• [ ] If the revert is to resolve a broken 'master' incident, please read through the Responsibilities of the Broken master resolution DRI.
• [ ] If the revert involves a database migration, please read through Deleting existing migrations.
• Add the appropriate labels before the MR is created. We can skip CI/CD jobs only if the labels are added before the CI/CD pipeline is created.

Milestone info

• I am reverting something in the current milestone. No changelog is needed, and I've added a ~"regression:*" label.
• [ ] I am reverting something in a different milestone. A changelog is needed, and I've removed the ~"regression:*" label.

Screenshots or screen recordings

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