[skip ci] fix broken link to CHANGELOG.MD

Author: Chris Wiechmann

UPDATE.md

@@ -96,7 +96,7 @@ Please follow the instructions to [import Kibana-Dashboards](README.md#kibana) b
 
 ### Parameters
 
-Sometimes it may be necessary to include newly introduced parameters in your `.env` file or you may want to use optional parameters. To do this, use the supplied `env-sample` as a reference and copy the desired parameters. Please check the [changelog](CHANGELOG.mb) which new parameters have been added.
+Sometimes it may be necessary to include newly introduced parameters in your `.env` file or you may want to use optional parameters. To do this, use the supplied `env-sample` as a reference and copy the desired parameters. Please check the [changelog](CHANGELOG.md) which new parameters have been added.
 
 ### Elastic-Stack version
 
@@ -175,4 +175,4 @@ The solution ships a defined Elasticsearch version with each release, which is u
 
 ### Can I skip several versions for an upgrade?
 
-Yes, you can. Please note which components have been updated between the current and the new version.
+Yes, you can. Please note which components have been updated between the current and the new version.