Bump guzzlehttp/guzzle from 7.8.1 to 7.13.1

Bumps [guzzlehttp/guzzle](https://github.com/guzzle/guzzle) from 7.8.1 to 7.13.1.
- [Release notes](https://github.com/guzzle/guzzle/releases)
- [Changelog](https://github.com/guzzle/guzzle/blob/7.13/CHANGELOG.md)
- [Commits](guzzle/guzzle@7.8.1...7.13.1)

---
updated-dependencies:
- dependency-name: guzzlehttp/guzzle
  dependency-version: 7.13.1
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

composer.json

@@ -19,7 +19,7 @@
     "ext-json": "*",
     "ext-openssl": "*",
     "ext-pdo": "*",
-    "guzzlehttp/guzzle": "^7.8.1",
+    "guzzlehttp/guzzle": "^7.13.1",
     "guzzlehttp/oauth-subscriber": "^0.6",
     "michelf/php-markdown": "^2",
     "pimple/pimple": "^3.5",