use custom ext::Opt for default_value in DeclStorageLine (#1722)

instead of ext::Seq

substrate/node/runtime/src/lib.rs

@@ -65,8 +65,8 @@ pub const VERSION: RuntimeVersion = RuntimeVersion {
 	spec_name: create_runtime_str!("node"),
 	impl_name: create_runtime_str!("substrate-node"),
 	authoring_version: 10,
-	spec_version: 23,
-	impl_version: 23,
+	spec_version: 24,
+	impl_version: 24,
 	apis: RUNTIME_API_VERSIONS,
 };