[doc] Fix a bug about booster api in the documentation.

[Fridge003]

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fixed #3897

📝 What does this PR do?

Fixed this bug by replacing Adam with HybridAdam in the documentation.

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[github-actions]

The code coverage for the changed files is 84%.

Click me to view the complete report

Name                            Stmts   Miss  Cover
---------------------------------------------------
colossalai/booster/booster.py      63     10    84%
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TOTAL                              63     10    84%