Fix bilibili (langchain-ai#4860)

# Fix bilibili api import error

bilibili-api package is depracated and there is no sync module.

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Fixes langchain-ai#2673 langchain-ai#2724 

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docs/modules/indexes/document_loaders/examples/bilibili.ipynb

@@ -23,7 +23,7 @@
    },
    "outputs": [],
    "source": [
-    "#!pip install bilibili-api"
+    "#!pip install bilibili-api-python"
    ]
   },
   {

langchain/document_loaders/bilibili.py

@@ -32,7 +32,7 @@ def _get_bilibili_subs_and_info(self, url: str) -> Tuple[str, dict]:
         except ImportError:
             raise ValueError(
                 "requests package not found, please install it with "
-                "`pip install bilibili-api`"
+                "`pip install bilibili-api-python`"
             )
 
         bvid = re.search(r"BV\w+", url)