修复查询时keyword可以为空

java/storlead-knowledge/storlead-knowledge-api/src/main/java/com/storlead/knowledge/api/ChunkController.java

@@ -32,7 +32,7 @@ public class ChunkController {
         String url = difyProperties.getBaseUrl()  + "datasets/"+ dataset_id +"/documents/"+document_id +"/segments";
         return httpService.get(
                 url,
-                Map.of("page", page.getPageIndex(), "size", page.getPageSize(), "keyword", page.getKeyword()),
+                page.getKeyword()==null?Map.of("page", page.getPageIndex(), "size", page.getPageSize()):Map.of("page", page.getPageIndex(), "size", page.getPageSize(), "keyword", page.getKeyword()),
                 "Bearer "+difyProperties.getDatasetApiKey(),
                 new TypeReference<>() {}
         );