uniform logger manager in FleetAPI.
hidde API under distributed/utils which users don't need.

* trim trailing whitespace

* fix `.cmake-format.py`

* revert npu ut changes, avoid npu ci error

* use yapf to format all python file

* yapf exclude two unittests file for they rely on writing and reading file, and format will break them

* disable diff_py_file because too many diff files cause command following failed

* [Auto Parallel] elastic support auto parallel re-launch

* [Auto Parallel] elastic support auto parallel re-launch

* fix ci issue

* fix ci issue

* fix rank mapping unittest

* fix rank mapping unittest

* fix ci issue

* fix ci issue

* fix ci issue

* fix ci issue

* fix ci issue

* fix ci issue

* fix ci issue

* fix ci issue

* fix ci issue

* fix ci issue

* fix ci issue

* fix ci issue

* fix ci issue

* fleet support elastic train

* fleet support elastic train

* support elastic

* add unittest

* fix unitest bug

* fix unittest bug

* fix unittest bug

* fix unittest coverage

* fix unittest coverage

* fix unittest coverage

* fix unittest coverage

* fix unittest coverage

* fix elastic bug

* fix ci fail

* fix ci fail

* fix elastic bug

* fix elastic bug

* fix joint debugging bug

* fix joint debugging bug

* fix windows ci failed

* fix windows ci failed

* Optimize fleet elastic scale in/out

* elastic support pre hook

* add prehook unittest

* fleet support elastic train

* fleet support elastic train

* support elastic

* add unittest

* fix unitest bug

* fix unittest bug

* fix unittest bug

* fix unittest coverage

* fix unittest coverage

* fix unittest coverage

* fix unittest coverage

* fix unittest coverage

* fix elastic bug

* fix ci fail

* fix ci fail

* fix elastic bug

* fix elastic bug

* fix joint debugging bug

* fix joint debugging bug

* fix windows ci failed

* fix windows ci failed

* fix force kill for elastic

* kill process by group

* add random and prevent deadlock

* elastic unitest

* rename demo

* elastic etcd ready