修复config不能指定Bug

Author: aimilin6688

weixin-java-mp/src/main/java/me/chanjar/weixin/mp/api/impl/WxMpPayServiceImpl.java

@@ -48,17 +48,13 @@ public class WxMpPayServiceImpl implements WxMpPayService {
     "REFUND_SOURCE_UNSETTLED_FUNDS"};
   private final Logger log = LoggerFactory.getLogger(this.getClass());
   private WxMpService wxMpService;
-  private WxMpConfigStorage config = null;
 
   public WxMpPayServiceImpl(WxMpService wxMpService) {
     this.wxMpService = wxMpService;
   }
 
   private WxMpConfigStorage getConfig() {
-    if (config == null) {
-      this.config = wxMpService.getWxMpConfigStorage();
-    }
-    return this.config;
+    return wxMpService.getWxMpConfigStorage();
   }
 
   @Override