update 国内标准-新增：标准编号输入示例

src/views/standardRegulationLibrary/domesticStandard/modules/DomesticStandardModal.vue

@@ -14,6 +14,9 @@
         <add-form ref="addForm"
                   :get-form-func="getFormFunc"
                   :get-document-info-func="getDocumentInfoFunc"
+                  :special-placeholder="{
+                    standard_number: `${$t('standardRegulationLibrary.inputExample')}7258`
+                  }"
                   @submitFormData="submitFormData" />
       </a-spin>
     </div>
@@ -28,7 +31,6 @@
 
 <script>
 import AddForm from '../../../../components/customField/AddForm.vue'
-import { postAction } from '@api/manage'
 import {
   getDomesticStandardDocumentInfo,
   getDomesticStandardFormModal,