[ArcGISOnline] Update CHANGELOG.md

Author: jbelien

src/Provider/ArcGISOnline/CHANGELOG.md

@@ -2,6 +2,17 @@
 
 The change log describes what is "Added", "Removed", "Changed" or "Fixed" between each release.
 
+## 4.2.0
+
+### Added
+
+- Add token authentication
+- Add support for `/geocodeAddresses` request (requires authentication)
+
+### Changed
+
+- Replace deprecated `/find` request by `/findAddressCandidates` request
+
 ## 4.1.0
 
 ### Removed