check is added for the report_to variable in TrainingArguments

[alpertunga-bile]

What does this PR do?

None, string and string array check is added for TrainingArgument structure's report_to variable in get_reporting_integration_callbacks function

Fixes #34445

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Who can review?

@SunMarc @muellerzr

[SunMarc]

LGTM ! Thanks !

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