add kwargs to all methods in the CallbackHandler class

[wilnn]

What does this PR do?

Add **kwargs to all methods in the CallbackHandler class. Previously, only the CallbackHandler.on_push_begin() method accepted **kwargs, while all other methods did not. This forces users who want to customize the Trainer class for their own use cases to modify methods in the CallbackHandler class, which is inconvenient. Adding **kwargs allows them to pass whatever they want to the CallbackHandler method calls and access those values in their own callback classes. Additionally, this makes the methods consistent with the template methods in TrainerCallback.

Fixes # (issue)

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@SunMarc

[Rocketknight1]

cc @SunMarc

[SunMarc]

SGTM

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