fix the document for the api multiply (#45304)
fix the document for the api multiply (#45304)

* update the document for the api multiply

* update the document for the api multiply; test=document_fix

* update the document for the api multiply; test=document_fix

* update the document for the api multiply; test=document_fix

* note;test=document_fix

Co-authored-by: Ligoml <7c429af8d8c8422b3749f86bdc79255f4dbaed32@users.noreply.github.com>
PaddlePaddle/Paddle,PaddlePaddle/Paddle,PaddlePaddle/Paddle,PaddlePaddle/Paddle,PaddlePaddle/Paddle,PaddlePaddle/Paddle,luotao1/Paddle,luotao1/Paddle,PaddlePaddle/Paddle,luotao1/Paddle,luotao1/Paddle,luotao1/Paddle,luotao1/Paddle,luotao1/Paddle