vesting_balance returns Option (#4987)

* `vesting_balance` returns `Option`

* bump impl

substrate/bin/node/runtime/src/lib.rs

@@ -81,7 +81,7 @@ pub const VERSION: RuntimeVersion = RuntimeVersion {
 	// and set impl_version to 0. If only runtime
 	// implementation changes and behavior does not, then leave spec_version as
 	// is and increment impl_version.
-	spec_version: 222,
+	spec_version: 223,
 	impl_version: 0,
 	apis: RUNTIME_API_VERSIONS,
 };