Drop redundant crypto gateway tests

tests/Service/Auth/AuthCryptoGatewayTest.php

@@ -1,34 +0,0 @@
-<?php
-
-namespace MintyPHP\Tests\Service\Auth;
-
-use MintyPHP\Service\Auth\AuthCryptoGateway;
-use PHPUnit\Framework\TestCase;
-
-final class AuthCryptoGatewayTest extends TestCase
-{
-    private AuthCryptoGateway $gateway;
-
-    protected function setUp(): void
-    {
-        if (!defined('APP_CRYPTO_KEY')) {
-            define('APP_CRYPTO_KEY', str_repeat('ab', 32));
-        }
-
-        $this->gateway = new AuthCryptoGateway();
-    }
-
-    public function testIsConfiguredReturnsTrueWhenKeyIsSet(): void
-    {
-        self::assertTrue($this->gateway->isConfigured());
-    }
-
-    public function testEncryptDecryptDelegatesToCrypto(): void
-    {
-        $plaintext = 'auth-secret';
-        $encrypted = $this->gateway->encryptString($plaintext);
-
-        self::assertNotSame($plaintext, $encrypted);
-        self::assertSame($plaintext, $this->gateway->decryptString($encrypted));
-    }
-}