Update phpstan/extension-installer requirement from ^1.4.2 to ^1.4.3 (#708)

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@1.4.2...1.4.3)

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

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

Author: dependabot[bot]

composer.json

@@ -28,7 +28,7 @@
     },
     "require-dev": {
         "php-parallel-lint/php-parallel-lint": "^1.4.0",
-        "phpstan/extension-installer": "^1.4.2",
+        "phpstan/extension-installer": "^1.4.3",
         "phpstan/phpstan": "^1.12.1",
         "phpstan/phpstan-phpunit": "^1.4.0",
         "phpunit/phpunit": "^8.5.38",