fix: UI tab name and reranking process for TeiFastReranking (#576)

* fix: update user-management.md

* fix: reranking process when TeiFastReranking is specified.

---------

Co-authored-by: Ryuichi Takano <45957617+tknrych@users.noreply.github.com>
Co-authored-by: Ryuichi Takano <ryuichi.takano@jp.ricoh.com>

libs/kotaemon/kotaemon/rerankings/tei_fast_rerank.py

@@ -29,13 +29,18 @@ class TeiFastReranking(BaseReranking):
         ),
     )
     is_truncated: Optional[bool] = Param(True, help="Whether to truncate the inputs")
+    max_tokens: Optional[int] = Param(512, help="This option is used to specify the maximum number of tokens supported by the reranker model.")
 
     def client(self, query, texts):
+        if self.is_truncated == True:
+                max_tokens = self.max_tokens # default is 512 tokens.
+                truncated_texts = [text[:max_tokens] for text in texts]
+
         response = session.post(
             url=self.endpoint_url,
             json={
                 "query": query,
-                "texts": texts,
+                "texts": truncated_texts,
                 "is_truncated": self.is_truncated,  # default is True
             },
         ).json()