Add Articles tests

tests/Feature/ArticlesRSSTest.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace Tests\Feature;
+
+use Tests\TestCase;
+use Illuminate\Foundation\Testing\WithoutMiddleware;
+use Illuminate\Foundation\Testing\DatabaseMigrations;
+use Illuminate\Foundation\Testing\DatabaseTransactions;
+
+class ArticlesRSSTest extends TestCase
+{
+    /**
+     * Test the RSS feed.
+     *
+     * @return void
+     */
+    public function test_rss_feed()
+    {
+        $response = $this->get('/feed');
+        $response->assertHeader('Content-Type', 'application/rss+xml');
+    }
+}