Reword section about UNRECOGNIZED to match the surrounding tone
Reword section about UNRECOGNIZED to match the surrounding tone

This paragraph alone seems to be phrased like "the rule does X in its suggested fix" instead of "you should do X".

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=300158501

cushon/error-prone,cushon/error-prone,google/error-prone,cushon/error-prone,google/error-prone,cushon/error-prone