[hotfix][docs] Translate cep.md

[lonecloud]

Signed-off-by: lonecloud lonecloud@aliyun.com

What is the purpose of the change

This pull request just translate the cep.md to Chinese. The original one had been tranlated few lines. I just finished the translation.

Brief change log

/docs/libs/cep.md

Verifying this change

Please see the final file.

Does this pull request potentially affect one of the following parts:

no

Documentation

Does this pull request introduce a new feature? ( no)

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Last check on commit b46fedf (Wed Sep 15 14:35:56 UTC 2021)

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