[ci] Bump cache key version (home-assistant#147148)

Author: cdce8p

.github/workflows/ci.yaml

@@ -37,7 +37,7 @@ on:
         type: boolean
 
 env:
-  CACHE_VERSION: 2
+  CACHE_VERSION: 3
   UV_CACHE_VERSION: 1
   MYPY_CACHE_VERSION: 1
   HA_SHORT_VERSION: "2025.6"