Update README.md

Author: mies

README.md

@@ -1,5 +1,7 @@
 ![GitHub_headerImage](https://user-images.githubusercontent.com/3262610/221191767-73b8a8d9-9f8b-440e-8ab6-75cb3c82f2bc.png)
 
+## Autometrics is no longer actively maintained.
+
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