Add site name validation test

tests/Feature/Settings/BrandingSettingsTest.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace Tests\Feature\Settings;
+
+use App\Models\User;
+use Tests\Support\InteractsWithSettings;
+use Tests\TestCase;
+
+class BrandingSettingsTest extends TestCase
+{
+    use InteractsWithSettings;
+
+    public function testSiteNameIsRequired()
+    {
+        $this->actingAs(User::factory()->superuser()->create())
+            ->post(route('settings.branding.save', ['site_name' => '']))
+            ->assertInvalid('site_name');
+    }
+}