doc: code-of-conduct

CODE_OF_CONDUCT.md

@@ -28,6 +28,7 @@ Examples of unacceptable behavior include:
 - Public or private harassment
 - Publishing others' private information, such as a physical or email address, without their explicit permission
 - **Spamming of any kind**
+- Aggressive sales tactics targeting our community members are strictly prohibited. You can mention your product if it's relevant to the discussion, but under no circumstances should you push it forcefully.
 - Other conduct which could reasonably be considered inappropriate in a professional setting
 
 ## Enforcement Responsibilities