[Website]: provide clarity on the take_over parameter on previous versions

[rodrigomadalozzo]

Type of issue

None

What documentation page is affected

https://www.elastic.co/docs/reference/beats/filebeat/migrate-to-filestream

What happened?

The new documentation format is "release agnostic," so I think we should have a warning or something in the 9.0 documentation, alerting that the use of take_over was different in previous versions, which were take_over: true, as stated in previous docs page. This may avoid future cases/SDHs.

Additional info

No response