Modify project name to rocketmq-client-cpp in CMakeList file

[ShannonDing]

What is the purpose of the change

Modify project name to rocketmq-client-cpp in CMakeList file

Brief changelog

Modify project name to rocketmq-client-cpp in CMakeList file

Verifying this change

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• Write necessary unit-test(over 80% coverage) to verify your logic correction, more mock a little better when a cross-module dependency exists.
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