Support parsing array in #param_to_integer_list (PR #14808)

This PR adds support for topic_ids to be passed as an array in the query parameter.

Context/Usecase: We pass topic_ids as an array to the /latest.json route to get select topics.

Expected Behaviour:


Current Behaviour: discourse errors out with internal server error.



#=> {"status":500,"error":"Internal Server Error"}


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This seems good to me, thanks.

Thank you for your review. Does this require any other changes for completion.

Sorry I was just waiting for CI to finish then forgot about it! It’s merged now. Thanks for following up.

Thank you for the merge! @eviltrout