[chat] refactor strategy class with booster api

[cwher]

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[github-actions]

The code coverage for the changed files is 89%.

Click me to view the complete report

Name                                                         Stmts   Miss  Cover
--------------------------------------------------------------------------------
colossalai/booster/booster.py                                   64     10    84%
colossalai/booster/mixed_precision/fp16_torch.py                46      2    96%
colossalai/booster/mixed_precision/mixed_precision_base.py       9      1    89%
colossalai/booster/plugin/gemini_plugin.py                     110      9    92%
colossalai/booster/plugin/low_level_zero_plugin.py              94      8    91%
colossalai/booster/plugin/plugin_base.py                        40     10    75%
colossalai/booster/plugin/torch_ddp_plugin.py                   66      3    95%
colossalai/booster/plugin/torch_fsdp_plugin.py                  97     13    87%
--------------------------------------------------------------------------------
TOTAL                                                          526     56    89%