docs: fix typo in content-creation-design/notification-content-creation

Author: suravshrestha

content-creation-design/notification-content-creation.mdx

@@ -192,7 +192,7 @@ You can:
 
 ## SMS
 
-When crafting your SMS notification, you can tap into all all the avaliable variables and even add dynamic ones.
+When crafting your SMS notification, you can tap into all all the available variables and even add dynamic ones.
 
 <img style={{ borderRadius: "0.5rem" }} src="/images/sms-editor.png" />