removing incorrect suggestion

aggregation with $out cannot span db's so it's not relevant here

Author: asya999

source/release-notes/4.0-compatibility.txt

@@ -290,12 +290,6 @@ As alternatives, users can:
 - Use :binary:`~bin.mongodump` and :binary:`~bin.mongorestore` or write
   a script using the drivers.
 
-- Use the aggregation pipeline with the :pipeline:`$out` stage for each
-  collection if copying a database from within the same deployment. The
-  output collection for the :pipeline:`$out` stage must be unsharded.
-  If the input collection is sharded, all documents for that collection
-  must be able to fit on the output collection's shard.
-
 Parameters
 ~~~~~~~~~~