Update guzzlehttp/guzzle requirement in the stable-updates group

Updates the requirements on [guzzlehttp/guzzle](https://github.com/guzzle/guzzle) to permit the latest version.

Updates `guzzlehttp/guzzle` to 8.0.0
- [Release notes](https://github.com/guzzle/guzzle/releases)
- [Changelog](https://github.com/guzzle/guzzle/blob/8.0/CHANGELOG.md)
- [Commits](guzzle/guzzle@7.9.0...8.0.0)

---
updated-dependencies:
- dependency-name: guzzlehttp/guzzle
  dependency-version: 8.0.0
  dependency-type: direct:production
  dependency-group: stable-updates
...

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

Author: dependabot[bot]

composer.json

@@ -14,7 +14,7 @@
         "ext-json": "*",
         "ext-openssl": "*",
         "ext-curl": "*",
-        "guzzlehttp/guzzle": "^7.9"
+        "guzzlehttp/guzzle": "^8.0"
     },
     "license": "MIT",
     "autoload": {