build(deps-dev): update phpstan/phpstan-deprecation-rules requirement (…

…#485)

Updates the requirements on [phpstan/phpstan-deprecation-rules](https://github.com/phpstan/phpstan-deprecation-rules) to permit the latest version.
- [Release notes](https://github.com/phpstan/phpstan-deprecation-rules/releases)
- [Commits](phpstan/phpstan-deprecation-rules@0.12.5...0.12.6)

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

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

composer.json

@@ -37,7 +37,7 @@
 		"mockery/mockery": "~1.2",
 		"phpstan/extension-installer": "1.1.0",
 		"phpstan/phpstan": "0.12.71",
-		"phpstan/phpstan-deprecation-rules": "0.12.5",
+		"phpstan/phpstan-deprecation-rules": "0.12.6",
 		"phpstan/phpstan-nette": "0.12.14",
 		"phpstan/phpstan-mockery": "0.12.11",
 		"phpstan/phpstan-strict-rules": "0.12.7",