* rename multi_tensor_adam to fused_adam

* fix some bugs

* fix CI coverage

* rename test_fused_adam.py

* fix some bug

* add test_fused_adam_op.py

* fix some bugs

* fix fused_adam_op.cc

* fix CI bugs

* fix CI bug

* fix CI bug

* add multi_tenosr_adam

* update multi_tensor_base.py, test_multi_tensor_adam.py, adamw.py

* fix adam.py optimizer.py

* fix adamw.py

* fix test_multi_tensor_adam.py

* fix CI bug

* fix CI coverage

* fix ci bug

* fix betapow

* fix some bugs

* fix test_adamw_op.py

* fix CI coverage

* fix multi_tensor_adam_kernel.cc

* fix CI bug

* fix multi_tensor_adam_op.cc and test_multi_tensor_adam.py

* fix code style

* update C++ parts

* remove python parts modification temporarily

* add C++ ut

* update betapow copy code logic

* fix ci ut

* fix windows ci

* fix coverage ci

* improve coverage rate

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Co-authored-by: Nsneaxiy <sneaxiy@126.com>