Update doc comment to fix wrong return type.

[naru-jpn]

Wrong type scalar was written in doc comment. Replaced it with actual type tensor.

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[saeta]

Thank you!

[saeta]

Hi @naru-jpn we just need you to sign the CLA before we can merge this. Can you do that and reply back to this thread per the instructions above? Thanks! -Brennan

[naru-jpn]

I signed it!!

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CLAs look good, thanks!

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[saeta]

Thank you @naru-jpn !