docs: add outbound reference link for Google icon article

Author: palakjaiswal16

blog/google-icon-update/index.md

@@ -175,6 +175,9 @@ Companies only fix long-standing UX complaints when something else is changing a
 
 Whether the new icons are beautiful or not matters less than whether they work. And by the only measure that actually counts, distinguishing one app from another in half a second, <span style={{color: 'red'}}> **the 2026 redesign works better than the 2020 one did.**</span>
 
+## References
+
+- [9to5Google: Google's new gradient icons for Gmail, Calendar, Drive, and other apps are radical redesigns](https://9to5google.com/2026/04/26/gmail-google-gradient-redesign/)
 
 
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