fix: pass expected error logging function to terminus (#671)

Author: bchrobot

src/server/index.js

@@ -198,7 +198,7 @@ createTerminus(server, {
   onSignal,
   beforeShutdown,
   onShutdown,
-  logger
+  logger: (msg, err) => logger.error(`${msg}: `, err)
 });
 
 getRunner().then(() => {