So after waiting for some time Microsoft finally released Microsoft Flow driven Page Approvals for Modern Pages in SharePoint.
What does this mean?
It means that if you turn this on on the SitePages library, the changes on the pages will not be published before someone will approve it.
It also supports the in page approval process, or that an flow is triggered to send an approval email to the approvers
To find out more visit Microsofts blog about this: