langchain: minor changes to StuffDocumentsChain._get_inputs (#15321)

Correcting a small typo ('the' instead of 'then') and changing another
'the' (instead of 'then' too, it was a hard day for the 'n' key :D) to
'also' to match better with what is done in the code

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libs/langchain/langchain/chains/combine_documents/stuff.py

@@ -182,8 +182,8 @@ class StuffDocumentsChain(BaseCombineDocumentsChain):
     def _get_inputs(self, docs: List[Document], **kwargs: Any) -> dict:
         """Construct inputs from kwargs and docs.
 
-        Format and the join all the documents together into one input with name
+        Format and then join all the documents together into one input with name
-        `self.document_variable_name`. The pluck any additional variables
+        `self.document_variable_name`. Also pluck any additional variables
         from **kwargs.
 
         Args: