Removed Swiftmailer dependency (#264)

Author: luke-

composer.json

@@ -17,7 +17,6 @@
  "php": ">=7.4.0",
  "yiisoft/yii2": "~2.0.14",
  "yiisoft/yii2-bootstrap4": "~2.0.0",
- "yiisoft/yii2-swiftmailer": "~2.0.0 || ~2.1.0",
  "yiisoft/yii2-symfonymailer": "~2.0.3"
  },
  "require-dev": {

config/test.php

@@ -17,6 +17,7 @@
  'db' => $db,
  'mailer' => [
  'useFileTransport' => true,
+ 'messageClass' => 'yii\symfonymailer\Message'
  ],
  'assetManager' => [
  'basePath' => __DIR__ . '/../web/assets',