Update contact section of CODE of CONDUCT (#9219)

Co-authored-by: Beta Ziliani <[email protected]>
Co-authored-by: Johannes Müller <[email protected]>

CODE_OF_CONDUCT.md

@@ -55,7 +55,7 @@ further defined and clarified by project maintainers.
 ## Enforcement
 
 Instances of abusive, harassing, or otherwise unacceptable behavior may be
-reported by opening an issue or contacting the project maintainers. All
+reported by contacting the project maintainers in private or by sending an email to [[email protected]](mailto:[email protected]). All
 complaints will be reviewed and investigated and will result in a response that
 is deemed necessary and appropriate to the circumstances. The project team is
 obligated to maintain confidentiality with regard to the reporter of an incident.