Update phpunit/phpunit requirement from ^8 || ^9 to ^8 || ^9 || ^10 (#25

)

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

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

composer.json

@@ -21,7 +21,7 @@
         }
     },
     "require-dev": {
-        "phpunit/phpunit": "^8 || ^9"
+        "phpunit/phpunit": "^8 || ^9 || ^10"
     },
     "scripts": {
         "test": "phpunit --testdox"