Merge pull request rails#54908 from sebaherrera07/update_rails_7_2_release_notes

Add ActiveRecord::Base.establish_connection behavior change to Rails 7.2 release notes [ci skip]

Author: byroot

guides/source/7_2_release_notes.md

@@ -478,6 +478,8 @@ Please refer to the [Changelog][active-record] for detailed changes.
 
 ### Notable changes
 
+*   `ActiveRecord::Base.establish_connection` no longer sets `ActiveRecord::Base.connection.active?` to `true`. If you need this behavior, you can use `ActiveRecord::Base.connection.verify!` instead.
+
 Active Storage
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