MAGETWO-51371: Wrong message in CLI output for installation

- changing way string append is done.

setup/src/Magento/Setup/Model/Installer.php

@@ -824,7 +824,7 @@ class Installer
             $this->log->log("Module '{$moduleName}':");
             $modulePostUpdater = $this->getSchemaDataHandler($moduleName, $handlerType);
             if ($modulePostUpdater) {
-                $this->log->logInline('Running ' + str_replace('-', ' ', $handlerType) + '...');
+                $this->log->logInline('Running ' . str_replace('-', ' ', $handlerType) . '...');
                 $modulePostUpdater->install($setup, $moduleContextList[$moduleName]);
             }
             $this->logProgress();