Fix wrong bytes per sample in TrackBass

[hwsmm]

BASS uses 16-bit samples by default if neither BassFlags.Byte nor BassFlags.Float is specified. (https://www.un4seen.com/doc/#bass/BASS_StreamCreate.html)

You can find this out by applying the following diff:

--- a/osu.Framework/Audio/Track/TrackBass.cs
+++ b/osu.Framework/Audio/Track/TrackBass.cs
@@ -15,6 +15,7 @@
 using osu.Framework.Extensions;
 using osu.Framework.Extensions.ObjectExtensions;
 using osu.Framework.Utils;
+using osu.Framework.Logging;

 namespace osu.Framework.Audio.Track
 {
@@ -106,6 +107,9 @@ internal TrackBass(Stream data, string name, bool quick = false)

                 bool success = seconds >= 0;

+                if (Bass.ChannelGetInfo(activeStream, out var info))
+                    Logger.Log($"Track Resolution: {info.Resolution}");
+
                 if (success)
                 {
                     Length = seconds * 1000;

Waveform will no longer bring the constant from TrackBass since Waveform still uses float samples.

[bdach]

How did you notice this? Does this have any meaningful impact on anything?

Not to say that it won't be merged even if it's correct, it probably will be merged after verification, just wondering how this would ever get spotted.

[hwsmm]

I could find because I have been working on #6002 which also uses BASS to decode, was just reading TrackBass and spotted this.

This PR probably has impact on nothing since the old value (4) was already correct enough since a sample frame has 2 channels.

[smoogipoo]

Lgtm. It used to have Float specified, but that caused issues with macOS.