Backports DOCSP-44273 to v8.0 (#465)

Backports #464 
[Jira](https://jira.mongodb.org/browse/DOCSP-44291)

Author: erabil-mdb

source/release-notes/changelogs/ops-manager/changelog-onprem-v8.0.rst

@@ -28,6 +28,7 @@ MongoDB Cluster Management
      are not supported when you use config shards.
 
 - Deprecates support for MongoDB 4.4 and MongoDB 5.0 deployments.
+- Deprecates support for MongoDB Server 6.0 as a :ref:`backing database <om-install-backing-dbs>`.
 - Removes support for MongoDB 4.2 deployments.
 
 Backup