public function testDeleteSuccess()
{
$category = factory(Category::class)->create();
$user = factory(App\User::class)->make(['hasRole' => true]);
Auth::login($user);
$res = $this->call('DELETE', "/categories/{$category->id}");
$this->assertEquals(204, $res->getStatusCode());
$exists = Category::find($category->id);
$this->assertNull($exists);
}