After cancelling a scheduled to publish page, it does not revert StartPublish date

Description

If scheduling is canceled, the published date remains as the scheduled date.

Steps to reproduce:

1. Create a page
2. Give it a published date in the past
3. Publish the page.
4. Update that page and schedule it to be published in the near future.
5. Remove the scheduling.

Expected:
The “Published” date should be restored to its original value from when it was previously published.

Actual:
The publish page keeps the scheduled date as the “Published” date.