refactor into getServiceConfig

src/mail.js

@@ -781,9 +781,7 @@ async function getMailAuth() {
 async function restartMail() {
     if (process.env.BOX_ENV === 'test' && !process.env.TEST_CREATE_INFRA) return;
 
-    const servicesConfig = await services.getConfig();
-    const mailConfig = servicesConfig['mail'] || {};
-
+    const mailConfig = services.getServiceConfig('mail');
     debug(`restartMail: restarting mail container with mailFqdn:${settings.mailFqdn()} mailDomain:${settings.mailDomain()}`);
     await configureMail(settings.mailFqdn(), settings.mailDomain(), mailConfig);
 }