fix: panics in find_columns_by_ids

[fuyufjh]

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What's changed and what's your intention?

See #15074 for background. The bugfix is simply changing remove() to get().

close #15074
close #15075

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[st1page]

checked the PR can solved #15075
(https://risingwave-labs.slack.com/archives/C048771BGKF/p1707471280469209?thread_ts=1707467013.682769&cid=C048771BGKF)