Fix broken transport.verify()

- chaining is failing 100%

src/services/email.service.js

@@ -5,10 +5,17 @@ const logger = require('../config/logger');
 const transport = nodemailer.createTransport(config.email.smtp);
 /* istanbul ignore next */
 if (config.env !== 'test') {
-  transport
-    .verify()
-    .then(() => logger.info('Connected to email server'))
-    .catch(() => logger.warn('Unable to connect to email server. Make sure you have configured the SMTP options in .env'));
+  transport.verify((error, success) => {
+    switch (true) {
+      case error:
+        logger.warn('Unable to connect to email server. Make sure you have configured the SMTP options in .env');
+        break;
+      case success:
+      default:
+        logger.info('Connected to email server');
+        break;
+    }
+  });
 }
 
 /**