fix core dump on aarch64

[USTCKAY]

parl在aarch64平台python3.9版本下训练模型时会出现free(): invalid pointer的错误继而发生core dump，原因在于parl安装的依赖1.37.0版本的grpcio在aarch64架构下会发生core dump。参考链接
此问题已在grpcio 1.38.1版本修复，故修改setup.py中依赖的grpcio版本以解决该bug。

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