Updates for CheckStyle 13.4

Author: AB-xdev

.config/checkstyle/checkstyle.xml

@@ -85,6 +85,7 @@
 			<property name="tokens" value=" CLASS_DEF"/>
 		</module>
 		<module name="IllegalImport"/>
+		<module name="IllegalSymbol"/>
 		<module name="InterfaceIsType"/>
 		<module name="JavadocStyle">
 			<property name="checkFirstSentence" value="false"/>