Update version to 3.0.0

Author: AlexxIT

custom_components/xiaomi_gateway3/manifest.json

@@ -13,6 +13,6 @@
   "requirements": [
     "zigpy>=0.42.0"
   ],
-  "version": "3.0a1",
+  "version": "3.0.0",
   "iot_class": "local_push"
 }