It seems that one of the main points of a code review had been missed: to learn something from it. The only thing you learned is that your colleague doesn't care for code quality, whereas he only learned that his lack of discipline is without consequence - which is not a good lesson whatsoever.
I agree with @rhymes
that you should take this to your managers. In the meantime, use the PRs for as much teaching/learning as possible.
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It seems that one of the main points of a code review had been missed: to learn something from it. The only thing you learned is that your colleague doesn't care for code quality, whereas he only learned that his lack of discipline is without consequence - which is not a good lesson whatsoever.
I agree with @rhymes that you should take this to your managers. In the meantime, use the PRs for as much teaching/learning as possible.