Update phpstan/phpstan-phpunit requirement from 1.1.1 to 1.2.2

Updates the requirements on [phpstan/phpstan-phpunit](https://github.com/phpstan/phpstan-phpunit) to permit the latest version.
- [Release notes](https://github.com/phpstan/phpstan-phpunit/releases)
- [Commits](phpstan/phpstan-phpunit@1.1.1...1.2.2)

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

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

composer.json

@@ -27,7 +27,7 @@
         "nepada/coding-standard": "7.6.0",
         "php-parallel-lint/php-parallel-lint": "1.3.2",
         "nette/tester": "2.4.3",
-        "phpstan/phpstan-phpunit": "1.1.1",
+        "phpstan/phpstan-phpunit": "1.2.2",
         "phpstan/phpstan-strict-rules": "1.4.4",
         "spaze/phpstan-disallowed-calls": "2.8.0",
         "shipmonk/phpstan-rules": "1.2.0",