build(deps-dev): update phpstan/phpstan requirement from 1.4.10 to 1.7.7

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/1.7.x/CHANGELOG.md)
- [Commits](phpstan/phpstan@1.4.10...1.7.7)

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

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

composer.json

@@ -36,7 +36,7 @@
 		"marc-mabe/php-enum": "~3.0",
 		"mockery/mockery": "~1.2",
 		"phpstan/extension-installer": "1.1.0",
-		"phpstan/phpstan": "1.4.10",
+		"phpstan/phpstan": "1.7.7",
 		"phpstan/phpstan-deprecation-rules": "1.0.0",
 		"phpstan/phpstan-nette": "1.0.0",
 		"phpstan/phpstan-mockery": "1.0.0",