Update phpunit/phpunit requirement from ^9.5.26 to ^10.3.4

Updates the requirements on [phpunit/phpunit](https://github.com/sebastianbergmann/phpunit) to permit the latest version.
- [Changelog](https://github.com/sebastianbergmann/phpunit/blob/10.3.4/ChangeLog-10.3.md)
- [Commits](sebastianbergmann/phpunit@9.5.26...10.3.4)

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

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

composer.json

@@ -43,7 +43,7 @@
     "require-dev": {
         "mockery/mockery": "^1.5",
         "orchestra/testbench": "^7.23|^8.1.1",
-        "phpunit/phpunit": "^9.5.26"
+        "phpunit/phpunit": "^10.3.4"
     },
     "config": {
         "sort-packages": true