.bitRate() not working

I added a case like this [PR ](https://github.com/jonataslaw/VideoCompress/pull/119/commits/ef123afb97023e984b1d4d6601de3accaed3b34a)and set .bitRate() in DefaultVideoStrategy. However, the bit rate of the output file does not change.
I want to compress it to an Instagram-like 720x720 video at around 600kbps.

```
8 -> {
videoTrackStrategy = DefaultVideoStrategy.Builder()
// .addResizer(AtMostResizer(720))
// .addResizer(ExactResizer(720,720))
// .bitRate(14400.toLong()) // not working
.bitRate(614400.toLong()) // not working
// .bitRate(204800) // not working
// .bitRate(1000) // not working
.frameRate(30)
// .frameRate(frameRate!!) // will be capped to the input frameRate
.build()
}
```

the bit rate of the output file is alway about 1500k regardless of the input bitrate value.