Fix build

Author: ondrejmirtes

tests/PHPStan/Rules/Pure/data/pure-method.php

@@ -399,8 +399,8 @@ public static function getB(): int
 
 class StaticMethodAssigningStaticProperty
 {
-	public static int $a = 0;
-
+	/** @var int */
+	public static $a = 0;
 	/**
 	 * @phpstan-pure
 	 */