Move Ada addon to deprecated addons (#2926)

Co-authored-by: Franck Nijhof <frenck@frenck.nl>

README.md

@@ -47,10 +47,6 @@ systems that have installed Home Assistant.
 
     A virtual personal assistant developed by Google.
 
-- **[Hey Ada!](/ada/README.md)**
-
-    Voice assistant powered by Home Assistant.
-
 - **[Let's Encrypt](/letsencrypt/README.md)**
 
     Manage an create certificates from Let's Encrypt.
@@ -89,6 +85,10 @@ systems that have installed Home Assistant.
 
 ### Deprecated Add-ons
 
+- **[Hey Ada!](/ada/README.md)**
+
+    Voice assistant powered by Home Assistant.
+
 - **[HomeMatic](/homematic/README.md)**
 
     HomeMatic central based on OCCU.