fix issue of "Auto-labeling while switching assets in asset preview causes an error" (#721)

Co-authored-by: Alex Chen <68627897+yongbing-chen@users.noreply.github.com>
Co-authored-by: alex-krasn <64093224+alex-krasn@users.noreply.github.com>
Co-authored-by: stew-ro <60453211+stew-ro@users.noreply.github.com>

src/services/assetService.ts

@@ -82,7 +82,7 @@ export class AssetService {
             return result;
         };
         const getLabelValues = (field: any) => {
-            return field.elements.map((path: string):IFormRegion => {
+            return field.elements?.map((path: string):IFormRegion => {
                 const pathArr = path.split('/').slice(1);
                 const word = pathArr.reduce((obj: any, key: string) => obj[key], { ...predictResults.analyzeResult });
                 return {