Add local static for stop characters

Author: JakeQZ

src/RuleSet/DeclarationBlock.php

@@ -45,16 +45,12 @@ public static function parse(ParserState $parserState, ?CSSList $list = null): ?
             $stringWrapperCharacter = null;
             $functionNestingLevel = 0;
             $consumedNextCharacter = false;
+            static $stopCharacters = ['{', '}', '\'', '"', '(', ')', ','];
             do {
                 if (!$consumedNextCharacter) {
                     $selectorParts[] = $parserState->consume(1);
                 }
-                $selectorParts[] = $parserState->consumeUntil(
-                    ['{', '}', '\'', '"', '(', ')', ','],
-                    false,
-                    false,
-                    $comments
-                );
+                $selectorParts[] = $parserState->consumeUntil($stopCharacters, false, false, $comments);
                 $nextCharacter = $parserState->peek();
                 $consumedNextCharacter = false;
                 switch ($nextCharacter) {