Update model card with v2 retrained metrics (macro F1: 0.42 -> 0.761)

Retrain with balanced data (19K examples) + WeightedTrainer: macro F1 0.42 -> 0.76

Retrain with balanced data (19K examples) + WeightedTrainer: macro F1 0.42 -> 0.761

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Upload RoBERTa-base intertextual classifier

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