Update phpstan/extension-installer requirement from 1.4.2 to 1.4.3 (#33)

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>

composer.json

@@ -25,7 +25,7 @@
 	"require-dev": {
 		"nette/tester": "~2.0",
 		"phpstan/phpstan": "1.12.0",
-		"phpstan/extension-installer": "1.4.2",
+		"phpstan/extension-installer": "1.4.3",
 		"phpstan/phpstan-strict-rules": "1.6.0"
 	},
 	"autoload": {