Update phpstan/phpstan requirement from 0.12.40 to 0.12.43

Updates the requirements on [phpstan/phpstan](https://github.com/phpstan/phpstan) to permit the latest version.
- [Release notes](https://github.com/phpstan/phpstan/releases)
- [Commits](phpstan/phpstan@0.12.40...0.12.43)

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

composer.json

@@ -35,7 +35,7 @@
         "nyholm/psr7": "^1.2",
         "php-http/curl-client": "^2.1",
         "phpstan/extension-installer": "^1.0",
-        "phpstan/phpstan": "0.12.40",
+        "phpstan/phpstan": "0.12.43",
         "phpstan/phpstan-phpunit": "0.12.16",
         "phpstan/phpstan-strict-rules": "0.12.4",
         "phpunit/phpunit": "~9.2.0",