Pass loss in model training callbacks

[arunppsg]

Description

I have updated callback to accept more metrics, like loss in this PR. This is a breaking change.

Type of change

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• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
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• Documentations (modification for documents)

Checklist

• My code follows the style guidelines of this project
  • Run yapf -i <modified file> and check no errors (yapf version must be 0.32.0)
  • Run mypy -p deepchem and check no errors
  • Run flake8 <modified file> --count and check no errors
  • Run python -m doctest <modified file> and check no errors
• I have performed a self-review of my own code
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• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• New unit tests pass locally with my changes
• I have checked my code and corrected any misspellings

[rbharath]

@arunppsg I don't want to make this a breaking change on the callbacks. Let's instead do a try/catch to gracefully handle the previous behavior as well

[arunppsg]

@rbharath the failures are not related to changes in this PR.

[shreyasvinaya]

@arunppsg can i rerun the torch tests, seems like torch is being fixed to a specific seed

[arunppsg]

sure, feel free to do it @shreyasvinaya

[rbharath]

LGTM