fix: 修复图片发送问题

[leochen-g]

No description provided.

[CLAassistant]

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[huan]

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[leochen-g]

Please make sure the following requirements have been met for your PR before we can continue reviewing it:

1. You have signed the CLA by clicking the [CLA | not signed yet] button from the comments.
2. The PR has passed all the CI tests and turns green. (you can execute all tests locally by running npm test)

因为测试用例使用的是 @huan 的测试号，但是现在测试号是不在线的，所以目前测试案例跑不通 😂

[huan]

LGTM

thanks for the improvements!