fix(equipment): 修复设备保养配置查询逻辑

jnpf-java-boot/jnpf-example/jnpf-example-controller/src/main/java/jnpf/controller/EqMainConfigController.java

@@ -55,6 +55,9 @@ public class EqMainConfigController {
     @GetMapping("/{id}")
     public ActionResult info(@PathVariable("id") Integer id) {
         EqMainConfigEntity entity = eqMainConfigService.getInfo(id);
+        if (entity == null) {
+            return ActionResult.fail("该设备保养配置不存在，请刷新界面！");
+        }
         if (entity != null) {
             Map<String, Object> result = JsonUtil.entityToMap(entity);