Follow below instructions
flutter pub run build_runner build --delete-conflicting-outputs -o web:build/web/; cp -f build/web/drift_worker.dart.js web/drift_worker.dart.js;
flutter pub run build_runner build --release --delete-conflicting-outputs -o web:build/web/; cp -f build/web/drift_worker.dart.js web/drift_worker.dart.min.js;