Update dependency guzzlehttp/guzzle to v8

| datasource | package           | from   | to    |
| ---------- | ----------------- | ------ | ----- |
| packagist  | guzzlehttp/guzzle | 7.12.3 | 8.0.0 |


Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

composer.json

@@ -38,7 +38,7 @@
     "require-dev": {
         "doctrine/migrations": "^2.0 || ^3.9.5",
         "enlightn/security-checker": "^1.10",
-        "guzzlehttp/guzzle": "^7.10.0",
+        "guzzlehttp/guzzle": "^8.0.0",
         "laminas/laminas-coding-standard": "~3.1.0",
         "mikey179/vfsstream": "^1.6.12",
         "php-amqplib/php-amqplib": "^2.0 || ^3.7.4",