Fix class name in test

"Class" is malform classname in PHP 7.

Author: zonuexe

tests/variables.php

@@ -3,6 +3,6 @@
 // Test highlighting of variables with the variable-name-face
 $regularVariable;
 $$variableVariable;
-Class::$staticVariable;
+MyClass::$staticVariable;
 $object->memberVariable;
 $object->funCall();