Update phpstan/extension-installer requirement from ^1.0 to ^1.1

Updates the requirements on [phpstan/extension-installer](https://github.com/phpstan/extension-installer) to permit the latest version.
- [Release notes](https://github.com/phpstan/extension-installer/releases)
- [Commits](phpstan/extension-installer@1.0...1.1.0)

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

composer.json

@@ -35,7 +35,7 @@
         "infection/infection": "^0.20.1",
         "nyholm/psr7": "^1.2",
         "php-http/curl-client": "^2.1",
-        "phpstan/extension-installer": "^1.0",
+        "phpstan/extension-installer": "^1.1",
         "phpstan/phpstan": "0.12.81",
         "phpstan/phpstan-phpunit": "0.12.18",
         "phpstan/phpstan-strict-rules": "0.12.9",