Docs: Changelog for SCALA-531

Author: rozza

docs/reference/content/changelog.md

@@ -14,6 +14,7 @@ Changes between released versions
   * Updated MongoDB Driver Async to 3.11.0
   * Updated DEFAULT_CODEC_REGISTRY order, as upstream BsonCodec captures all Bson instances and priority needs to be lower.
   * Support $merge pipeline stage in aggregations [SCALA-473](https://jira.mongodb.org/browse/SCALA-473)
+  * Deprecated BsonArray.apply(Iterable[BsonValue]) added BsonArray.fromIterable [SCALA-531](https://jira.mongodb.org/browse/SCALA-531)
 
 ### 2.6.0
   * Updated MongoDB Driver Async to 3.10.0