logs: simplify config file missing error

lib/config/file.js

@@ -15,7 +15,7 @@ function getConfig(env) {
     config = require(configFile);
   } catch (err) {
     // Do nothing
-    logger.debug('Could not locate config file');
+    logger.debug('No config file found on disk - skipping');
   }
   return config;
 }