Update phpmailer/phpmailer requirement from 6.11.1 to 7.0.0 in /lib (#8180)

* Update phpmailer/phpmailer requirement from 6.11.1 to 7.0.0 in /lib

Updates the requirements on [phpmailer/phpmailer](https://github.com/PHPMailer/PHPMailer) to permit the latest version.
- [Release notes](https://github.com/PHPMailer/PHPMailer/releases)
- [Changelog](https://github.com/PHPMailer/PHPMailer/blob/master/changelog.md)
- [Commits](https://github.com/PHPMailer/PHPMailer/compare/v6.11.1...v7.0.0)

---
updated-dependencies:
- dependency-name: phpmailer/phpmailer
  dependency-version: 7.0.0
  dependency-type: direct:production
...

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

* composer update

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Alexandre Alapetite <alexandre@alapetite.fr>

lib/composer.json

@@ -13,7 +13,7 @@
     "require": {
         "marienfressinaud/lib_opml": "0.5.1",
         "phpgt/cssxpath": "v1.4.0",
-        "phpmailer/phpmailer": "6.11.1",
+        "phpmailer/phpmailer": "7.0.0",
         "simplepie/simplepie": "dev-freshrss#24cfb0c6d81f81ef110c8257d3464b2649476c77"
     },
     "config": {

lib/phpmailer/phpmailer/README.md

@@ -48,7 +48,7 @@ This software is distributed under the [LGPL 2.1](https://www.gnu.org/licenses/o
 PHPMailer is available on [Packagist](https://packagist.org/packages/phpmailer/phpmailer) (using semantic versioning), and installation via [Composer](https://getcomposer.org) is the recommended way to install PHPMailer. Just add this line to your `composer.json` file:
 
 ```json
-"phpmailer/phpmailer": "^6.11.1"
+"phpmailer/phpmailer": "^7.0.0"
 ```
 
 or run

lib/phpmailer/phpmailer/VERSION

@@ -1 +1 @@
-6.11.1
+7.0.0

lib/phpmailer/phpmailer/src/PHPMailer.php

@@ -768,7 +768,7 @@ class PHPMailer
      *
      * @var string
      */
-    const VERSION = '6.11.1';
+    const VERSION = '7.0.0';
 
     /**
      * Error severity: message only, continue processing.

lib/phpmailer/phpmailer/src/SMTP.php

@@ -35,7 +35,7 @@ class SMTP
      *
      * @var string
      */
-    const VERSION = '6.11.1';
+    const VERSION = '7.0.0';
 
     /**
      * SMTP line break constant.