Update yiisoft/yii2-symfonymailer requirement from ^3.0 to ^4.0

Updates the requirements on [yiisoft/yii2-symfonymailer](https://github.com/yiisoft/yii2-symfonymailer) to permit the latest version.
- [Release notes](https://github.com/yiisoft/yii2-symfonymailer/releases)
- [Changelog](https://github.com/yiisoft/yii2-symfonymailer/blob/master/CHANGELOG.md)
- [Commits](yiisoft/yii2-symfonymailer@3.0.0...4.0.0)

---
updated-dependencies:
- dependency-name: yiisoft/yii2-symfonymailer
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

composer.json

@@ -20,7 +20,7 @@
         "yii2-extensions/bootstrap5": "dev-main",
         "yiisoft/config": "^1.4",
         "yiisoft/yii2": "^2.2",
-        "yiisoft/yii2-symfonymailer": "^3.0"
+        "yiisoft/yii2-symfonymailer": "^4.0"
     },
     "require-dev": {
         "codeception/c3": "^2.8",