add screenshot

Author: yume-chan

blog/2024-10-8-link-sign-in-methods/index.mdx

@@ -27,6 +27,8 @@ Here's how to use it:
 
 From next time, sign in using both methods will log you in to the same account.
 
+![Settings Dialog](settings.png)
+
 ## Warning on connect to existing account
 
 If you already have multiple Tango accounts via multiple sign-in methods, you can still connect those sign-in methods to one Tango account. But to be aware, you will lose the access to the other accounts.