composer(deps-dev): update phpstan/phpstan requirement from ^1.8.3 to…

… ^1.8.4 (#67)

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

Updates the requirements on [phpstan/phpstan](https://github.com/phpstan/phpstan) to permit the latest version.
- [Release notes](https://github.com/phpstan/phpstan/releases)
- [Changelog](https://github.com/phpstan/phpstan/blob/1.8.x/CHANGELOG.md)
- [Commits](phpstan/phpstan@1.8.3...1.8.4)

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

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

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

composer.json

@@ -25,7 +25,7 @@
   "require-dev": {
     "mimmi20/coding-standard": "^3.0.10",
     "phpstan/extension-installer": "^1.1.0",
-    "phpstan/phpstan": "^1.8.3",
+    "phpstan/phpstan": "^1.8.4",
     "phpstan/phpstan-deprecation-rules": "^1.0.0",
     "phpstan/phpstan-phpunit": "^1.1.1",
     "phpunit/phpunit": "^9.5.24"