Bug Fix: use iloc to index pd.Series

[bekojuniranjan]

Proposed changes

There was a key error in indexing pandas series in scatter_plot_summary_holdout. It is a simple issue, but it terminates the execution. And, it is solved using the iloc operator of pandas.

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[CLAassistant]

All committers have signed the CLA.

[jeongyoonlee]

Hi @bekojuniranjan. Can you sign the CLA so that we can accept your PR?

[bekojuniranjan]

Hi @bekojuniranjan. Can you sign the CLA so that we can accept your PR?

I don't realise I have to sign the CLA. Now, it's done.

[jeongyoonlee]

LGTM