[Here] Update CHANGELOG.md

Author: jbelien

src/Provider/Here/CHANGELOG.md

@@ -2,6 +2,12 @@
 
 The change log describes what is "Added", "Removed", "Changed" or "Fixed" between each release.
 
+## 0.5.0
+
+### Added
+
+- Support API key (see [documentation](https://developer.here.com/documentation/authentication/dev_guide/topics/api-key-credentials.html))
+
 ## 0.4.0
 
 ### Removed