Function finish

tests/margin-ws-api-live.test.ts:65–71

(err?: Error)

        let finished = false;

        const finish = (err?: Error) => {
            if (finished) return;
            finished = true;
            stopWsApiConnections();
            if (err) return done(err);
            done();
        };

        binance.websockets.userMarginData(
            // all_updates_callback