unify cs fixer config

.php-cs-fixer.dist.php

@@ -33,6 +33,7 @@
         'blank_line_before_statement' => [
             'statements' => ['break', 'continue', 'declare', 'return', 'throw', 'exit'],
         ],
+        'final_internal_class' => false,
         'combine_consecutive_issets' => false,
         'combine_consecutive_unsets' => false,
         'multiline_whitespace_before_semicolons' => false,