node-redis v4 ReplyError: ERR Error running script
Hello, I got a weird exception after implementing `RateLimiterRedis` like in your wiki: https://github.com/animir/node-rate-limiter-flexible/wiki/Redis

Here is the exception I got:
```
ReplyError: ERR Error running script (call to f_a1de965f42e177aa339706bd580f049065eca79a): @user_script:1: @user_script: 1: Lua redis() command arguments must be strings or integers
```

Here is my code:
```js
async consume(ip) {
    if (!this.limiter) return;

    let res = false;

    try {
        res = await this.limiter.consume(ip);
    } catch (e) {
        if (e instanceof Error) {
            console.log("RATE LIMITER ERROR:", e.message);
        } else {
            return false;
        }
    }

    return res;
}
```

**rate-limiter-flexible version:** 2.3.1
**redis version:** 4.0.0-rc.2