Prepare documentation (Puppet Platform 7.20.0)

(Initial planned release date: 2022-10-11)

Write release notes for the release based on the tickets found in the previous step:

• Search for tickets with fixVersion = "SERVER 7.9.2": https://tickets.puppetlabs.com/secure/IssueNavigator.jspa?jql=fixVersion="SERVER 7.9.2"
• Check each ticket's DOCS tab for the necessary release notes.
• Open a PR in the osp-docs repo. Target the PR against the *-preview branch corresponding to the major Platform version (or latest-preview).
• NOTE: These docs should not be published to the main site until release day.