update phel-config.php default config example

Author: Chemaclass

content/documentation/configuration.md

@@ -21,7 +21,7 @@ return (new \Phel\Config\PhelConfig())
     ->setNoCacheWhenBuilding([])
     ->setFormatDirs(['src', 'tests'])
     ->setKeepGeneratedTempFiles(false)
-	->setTempDir(sys_get_temp_dir().'/phel')
+    ->setTempDir(sys_get_temp_dir().'/phel')
     ->setBuildConfig((new \Phel\Config\PhelBuildConfig())
         ->setMainPhelNamespace('your-ns\index')
         ->setMainPhpPath('out/index.php'))