[CI] 【Hackathon 9th Sprint No.33】NO.33 功能模块单测补充 (PaddlePaddle#5056)

* Add cache messager unit tests

* Refactor test_cache_messager.py with new stubs

Updated copyright information and modified function names for clarity.

* Add missing stubs for cache messager tests

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Co-authored-by: Tao Luo <luotao02@baidu.com>

Author: xunyoyo