In tutorial notebooks: Loading model arg split changed to splitter

[yihuajack]

Pull Request Template

Description

Fix #3273

'split' is deprecated. Use 'splitter' instead.

Also fix the wrong Google Colab link of Advanced_model_training_using_hyperopt.ipynb

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

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  • Run yapf -i <modified file> and check no errors (yapf version must be 0.32.0)
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[rbharath]

Thanks for the contribution! Could you split this PR up into multiple PRs? For new developers, I usually recommend not changing more than one tutorial at a time; it becomes too hard to review for us.

[yihuajack]

How to split one PR into multiple PRs? Sorry I have not done this before

This PR only modifies code

• the split argument to splitter in the listed 6 notebooks, each notebook only 1 change
• the Google Colab link of Advanced_model_training_using_hyperopt.ipynb

Some of the notebooks include outputs using old versions of deepchem. To test whether the above modifications change the results, I ran those notebooks to check whether the outputs make the same sense as before. If needed, the debugging information of the outputs like the progress of installing packages can be removed.

[rbharath]

You can make a fresh PR and copy in a subset of changes. If you have questions, can you come by office hours (9am PST every weekday) https://forum.deepchem.io/t/announcing-the-deepchem-office-hours/293

[yihuajack]

OK, I'll make a fresh PR and close this one