fix: use Mapping instead of dict for EvalResult.scores#360

Abhijeet Prasad (AbhiPrasad) merged 1 commit intomainbraintrustdata/braintrust-sdk-python:mainfrom

fix/eval-result-scores-mappingbraintrustdata/braintrust-sdk-python:fix/eval-result-scores-mappingCopy head branch name to clipboard