Laravel 10.x - A facade root has not been set.解决办法

今天在laravel单元测试中使用Http请求接口时，报错显示A facade root has not been set.

默认单元测试的代码是这样的

<?php

namespace Tests\Unit;

use Illuminate\Support\Facades\Http;
use PHPUnit\Framework\TestCase;
use Tests\CreatesApplication;

class ExampleTest extends TestCase
{
   
   
    /**
     * A basic test example.
     */
    public function test_that_true_is_true(): void
    {
   
   
        $resp= Http::get('https://b.exam