Convert scalars to 1D to satisfy ML Program requirements. (#21159)
### Description
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Convert scalars to 1D to satisfy ML Program requirements.
https://dev.azure.com/onnxruntime/onnxruntime/_build/results?buildId=1418617&view=logs&j=f7cc61a9-cc70-56e7-b06c-4668ca17e426&t=16d281b5-1bfd-5309-f274-36d0dffd9cb1&l=27167
### Motivation and Context
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Fixes test failure in #17361