Docs: Edit pinecone example (#1154)

```
// Add the documents
vectorStore.add(List.of(document));
```
To
```
// Add the documents
vectorStore.add(documents);
```

Author: JayPark7821

spring-ai-docs/src/main/antora/modules/ROOT/pages/api/vectordbs/pinecone.adoc

@@ -226,7 +226,7 @@ Add the documents to Pinecone:
 
 [source,java]
 ----
-vectorStore.add(List.of(document));
+vectorStore.add(documents);
 ----
 
 And finally, retrieve documents similar to a query: