Update release-notes/v6.0.0

Author: mpkorstanje

release-notes/v6.0.0.md

@@ -65,7 +65,7 @@ The old html formatter has been replaced with an improved html formatter that
 outputs the entire report as single file rather than a collection of files.
 
 ```java
-@CucumberOptions(plugin = "message:target/cucumber-report.html")
+@CucumberOptions(plugin = "html:target/cucumber-report.html")
 ```
 
 Note: If you are already using the html formatter. Do not forget to append