update Services::pager() to use pull Pager Config by config("Pager") as well if no config passed

Author: samsonasik

system/Config/Services.php

@@ -500,7 +500,7 @@ public static function pager($config = null, RendererInterface $view = null, boo
 
 		if (empty($config))
 		{
-			$config = new \Config\Pager();
+			$config = config('Pager');
 		}
 
 		if (! $view instanceof RendererInterface)

tests/system/Database/Live/ModelTest.php

@@ -1345,19 +1345,13 @@ public function testPaginateChangeConfigPager()
 		$perPage                 = config('Pager')->perPage;
 		config('Pager')->perPage = 1;
 
-		// ensure new instance for new "perPage" config from config('Pager')
-		\Config\Services::pager(config('Pager'), null, true);
-
 		$model = new ValidModel($this->db);
 
 		$data = $model->paginate();
 
 		$this->assertEquals(1, count($data));
 
 		config('Pager')->perPage = $perPage;
-
-		// rollback to use same instance on call
-		\Config\Services::pager(config('Pager'), null, false);
 	}
 
 	//--------------------------------------------------------------------