bump slevomat/coding-standard

Author: schlndh

composer.json

@@ -28,7 +28,7 @@
 		"ext-mysqli": "*",
 		"phpunit/phpunit": "^9.6.22",
 		"squizlabs/php_codesniffer": "^3.7",
-		"slevomat/coding-standard": "~8.19.0",
+		"slevomat/coding-standard": "~8.20.0",
 		"phpstan/phpstan-phpunit": "^2.0",
 		"phpstan/phpstan-deprecation-rules": "^2.0",
 		"phpstan/phpstan-strict-rules": "^2.0"