Release koi-6652 (#1569)

Author: aurexav

.github/note-template/runtime.md

@@ -1,6 +1,5 @@
 ## {{ .Env.CHAIN | strings.Title }}
-<h3 align="right">Upgrade Priority HIGH :red_circle:</h3>
-<h4 align="center">!!All nodes must be upgraded to a minimum of `v6.6.4` version because of the new asynchronous backing feature!!</h4>
+<h3 align="right">Upgrade Priority LOW :green_circle:</h3>
 
 #### Whitelist Hash
 ```

runtime/koi/src/lib.rs

@@ -80,7 +80,7 @@ pub const VERSION: sp_version::RuntimeVersion = sp_version::RuntimeVersion {
 	spec_name: sp_runtime::create_runtime_str!("Darwinia Koi"),
 	impl_name: sp_runtime::create_runtime_str!("DarwiniaOfficialRust"),
 	authoring_version: 0,
-	spec_version: 6_6_5_1,
+	spec_version: 6_6_5_2,
 	impl_version: 0,
 	apis: RUNTIME_API_VERSIONS,
 	transaction_version: 0,