plugins.nicolive: fix quality
plugins.nicolive: fix quality

```
$ streamlink "https://live2.nicovideo.jp/watch/lv327858775"
[cli][info] Found matching plugin nicolive for URL https://live2.nicovideo.jp/watch/lv327858775
[cli][info] Available streams: 3600k (worst, best)
[cli][info] Opening stream: 3600k (hls)
```

now

```
$ streamlink "https://live2.nicovideo.jp/watch/lv327858775"
[cli][info] Found matching plugin nicolive for URL https://live2.nicovideo.jp/watch/lv327858775
[cli][info] Available streams: 345k (worst), 691k, 1800k, 3600k, 5400k (best)
[cli][info] Opening stream: 5400k (hls)
```

melmorabity/streamlink,chhe/streamlink,gravyboat/streamlink,chhe/streamlink,gravyboat/streamlink,bastimeyer/streamlink,beardypig/streamlink,melmorabity/streamlink,bastimeyer/streamlink,beardypig/streamlink,streamlink/streamlink,streamlink/streamlink