chore: add jooq example

Author: hantsy

data-jdbc-jooq/src/main/java/com/example/OrderRepository.java

@@ -1,5 +1,6 @@
 package com.example;
 
+import jakarta.inject.Singleton;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.jooq.DSLContext;
@@ -14,6 +15,7 @@
 
 @RequiredArgsConstructor
 @Slf4j
+@Singleton
 public class OrderRepository {
     private final DSLContext dslContext;