MAGETWO-88409: Builds stabilization for PR

- tests fix

Author: rganin

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

@@ -360,7 +360,6 @@ public function install($request)
         $script[] = ['Post installation file permissions check...', 'checkApplicationFilePermissions', []];
         $script[] = ['Write installation date...', 'writeInstallationDate', []];
         $estimatedModules = $this->createModulesConfig($request, true);
-        $this->objectManagerProvider->reset();
         $total = count($script) + 4 * count(array_filter($estimatedModules));
         $this->progress = new Installer\Progress($total, 0);