MONGOID-5366 add fix to 7.3.5 release notes

Author: p

source/release-notes/mongoid-7.3.txt

@@ -298,3 +298,11 @@ Mongoid 7.2 behavior:
   Band.count # => 1
   Mongoid.purge! # or Mongoid.truncate!
   Band.count # => 1
+
+
+``update_one`` Warnings in ``upsert``
+-------------------------------------
+
+Mongoid 7.3.5 fixes incorrect usage of the driver's ``update_one`` method from
+Mongoid's ``upsert`` method. Mongoid's ``upsert`` actually performs a
+replacing upsert, and Mongoid 7.3.5 and later correctly call ``replace_one``.