[New] Migrating from Self-Hosted to Managed Databases (#7264)

* [New] Migrating from Self-Hosted to Managed Databases

* added content for level access, configurations, extensions and plugins, and backups sections

* copy edits and add version control content

* copy edits, add final sections and contents, add screenshots

* copy edits

* URL and title change, copy edits

Author: jddocs

ci/vale/dictionary.txt

@@ -533,6 +533,7 @@ delpy
 demultiplexer
 Deno
 denormalized
+denylist
 deprovision
 deprovisioning
 deque
@@ -1358,6 +1359,7 @@ linodego
 linodes
 linroot
 linter
+Liquibase
 lish
 liskov
 listdir