Update ChangeLog.md

Author: oshai

ChangeLog.md

@@ -11,7 +11,7 @@ and [maven central](https://repo1.maven.org/maven2/io/github/oshai/kotlin-loggin
 
 # Overview 
 
-The latest kotlin-logging version is 5.  
+The latest kotlin-logging version is 6.  
 It is the recommended version for new users and upgrades, as previous versions will require manual upgrade.
 
 Version 4.x is **not recommended** to use (we jumped directly from v.3 to v.5).  
@@ -31,6 +31,17 @@ In that sense it's a completely new dependency.
 
 Below is a list of all versions, some history and note-worthy changes.
 
+# Version 6
+
+Released on: Dec 18, 2023.  
+Full change log: 
+[v.6](https://github.com/oshai/kotlin-logging/releases/tag/6.0.0).
+
+Main changes are:
+
+- Support kotlin version >= 1.9.
+- Change to depend on KMP 1.9.
+
 # Version 5
 
 Released on: July 19, 2023.