Fix enum serialization in CaseBuilder for Hibernate compatibility

Author: 차동민/BE/GN

querydsl-libraries/querydsl-jpa/src/main/java/com/querydsl/jpa/JPQLSerializer.java

@@ -383,6 +383,10 @@ private void serializeSources(boolean forCountRow, List<JoinExpression> joins) {
 
   @Override
   public void visitConstant(Object constant) {
+    if (constant instanceof Enum) {
+      visitLiteral(constant);
+      return;
+    }
     if (inCaseOperation && templates.isCaseWithLiterals()) {
       if (constant instanceof Collection) {
         append("(");

querydsl-libraries/querydsl-jpa/src/main/java/com/querydsl/jpa/JPQLTemplates.java

@@ -213,7 +213,7 @@ public String asLiteral(Object constant) {
     } else if (constant instanceof String) {
       return "'" + escapeLiteral(constant.toString()) + "'";
     } else if (constant instanceof Enum) {
-      return constant.getClass().getName() + "." + ((Enum) constant).name();
+      return "'" + ((Enum<?>) constant).name() + "'";
     } else {
       return "'" + constant.toString() + "'";
     }