fix:npe

src/main/java/cn/com/poc/knowledge/rest/impl/KnowledgeRestImpl.java

@@ -220,6 +220,9 @@ public class KnowledgeRestImpl implements KnowledgeRest {
         List<QueryKnowledgeDocumentDto> result = new ArrayList<>();
         for (Integer knowledgeInfoId : knowledgeInfoIds) {
             BizKnowledgeInfoEntity bizKnowledgeInfoEntity = bizKnowledgeInfoService.get(knowledgeInfoId);
+            if (bizKnowledgeInfoEntity == null) {
+                continue;
+            }
             QueryKnowledgeDocumentDto dto = new QueryKnowledgeDocumentDto();
             BeanUtil.copyProperties(bizKnowledgeInfoEntity, dto);
             List<Integer> kdIdList = JsonUtils.deSerialize(bizKnowledgeInfoEntity.getKdIds(), new TypeReference<List<Integer>>() {