Fix get_products_by_ownership to always return an array

[IanRamosC]

Proposed changes:

• This PR fixes the return of get_products_by_ownership so both owned and unowned products always return an array.

Other information:

• Have you written new tests for your changes, if applicable?
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Testing instructions:

• N/a

[github-actions]

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[github-actions]

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[robertsreberski]

Looks good!