change "使用流程" translation

Done

Author: shanyi15

doc/v2/getstarted/index_en.rst

@@ -10,7 +10,7 @@ If you want to quickly know how to use PaddlePaddle, please refer to the followi
 
 
 While using PaddlePaddle to build applications, please understand some basic concepts.
-Here is an example of linear regression. It introduces use flow of PaddlePaddle, including data format, model configuration and training, etc.
+Here is an example of linear regression. It introduces workflow of PaddlePaddle, including data format, model configuration and training, etc.
 
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