Simplify a SuppressWarnings annotation

src/main/java/org/sablecc/sablecc/lexer/LexerException.java

@@ -2,7 +2,7 @@
 
 package org.sablecc.sablecc.lexer;
 
-@SuppressWarnings({"serial"})
+@SuppressWarnings("serial")
 public class LexerException extends Exception
 {
     private final int line;

src/main/resources/org/sablecc/sablecc/lexer.txt

@@ -10,7 +10,7 @@ Macro:LexerException
 
 package $0$lexer;
 
-@SuppressWarnings({"serial"})
+@SuppressWarnings("serial")
 public class LexerException extends Exception
 {
     private final int line;