composer(deps-dev): update phpunit/phpunit requirement

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

Updates `phpunit/phpunit` to 10.5.26
- [Release notes](https://github.com/sebastianbergmann/phpunit/releases)
- [Changelog](https://github.com/sebastianbergmann/phpunit/blob/10.5.26/ChangeLog-10.5.md)
- [Commits](sebastianbergmann/phpunit@10.5.25...10.5.26)

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

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

composer.json

@@ -37,7 +37,7 @@
     "phpstan/phpstan": "^1.11.7",
     "phpstan/phpstan-deprecation-rules": "^1.2.0",
     "phpstan/phpstan-phpunit": "^1.4.0",
-    "phpunit/phpunit": "^10.5.25",
+    "phpunit/phpunit": "^10.5.26",
     "rector/rector": "^1.2.0",
     "rector/type-perfect": "^0.1.8",
     "symplify/phpstan-rules": "^13.0.0",