fix: Change the data in the dataset page to be obtained using the interface (#8726)

### What problem does this PR solve?

Change the data in the dataset page to be obtained using the interface,
and change the import to obtain all data every 15 seconds to obtain the
data of the current page every 5 seconds when parsing the existing file.
[#3221](https://github.com/infiniflow/ragflow/issues/3221)

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

web/src/pages/dataset/testing/index.tsx

@@ -35,9 +35,8 @@ export default function RetrievalTesting() {
     <div className="p-5">
       <section className="flex justify-between items-center">
         <TopTitle
-          title={'Configuration'}
-          description={`  Update your knowledge base configuration here, particularly the chunk
-                  method.`}
+          title={'Retrieval testing'}
+          description={`Conduct a retrieval test to check if RAGFlow can recover the intended content for the LLM.`}
         ></TopTitle>
         {/* <Button>Save as Preset</Button> */}
       </section>