Update phpunit/phpunit requirement from ^10.0 to ^10.0 || ^11.0

Updates the requirements on [phpunit/phpunit](https://github.com/sebastianbergmann/phpunit) to permit the latest version.
- [Release notes](https://github.com/sebastianbergmann/phpunit/releases)
- [Changelog](https://github.com/sebastianbergmann/phpunit/blob/11.4.2/ChangeLog-11.4.md)
- [Commits](sebastianbergmann/phpunit@10.0.0...11.4.2)

---
updated-dependencies:
- dependency-name: phpunit/phpunit
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <[email protected]>

composer.json

@@ -39,7 +39,7 @@
         "php-http/mock-client": "^1.5",
         "php-soap/ext-soap-engine": "^1.7",
         "php-soap/engine-integration-tests": "^1.9",
-        "phpunit/phpunit": "^10.0",
+        "phpunit/phpunit": "^10.0 || ^11.0",
         "guzzlehttp/guzzle": "^7.5"
     },
     "config": {