Fixed static keyword

Author: cheestree

liquidjava-example/src/main/java/testSuite/ErrorChars.java

@@ -3,7 +3,7 @@
 import liquidjava.specification.Refinement;
 
 public class ErrorChars {
-    void printLetter(@Refinement("_ >= 65 && _ <= 90 || _ >= 97 && _ <= 122") char c) {
+    static void printLetter(@Refinement("_ >= 65 && _ <= 90 || _ >= 97 && _ <= 122") char c) {
         System.out.println(c);
     }