[MC-272891] Floating Dream is louder in Lush Caves

The song Floating Dream is set to 0.4 volume in four of its five sound events. However, in the music.overworld.lush_caves sound event, the song is set to full volume.

Sound Event	floating_dream Volume
music.game	0.4
music.overworld.forest	0.4
music.overworld.jagged_peaks	0.4
music.overworld.lush_caves	1.0
music.overworld.old_growth_taiga	0.4

In addition, the Bedrock version of this sound event uses 0.4 as the Floating Dream volume, making this a parity issue.

To Reproduce

Open the 1.21 pre2 sounds.json file.
Search for all occurrences of the string "floating_dream".
Notice every occurrence uses a 0.4 volume except lush_caves.

Expected Result

Floating Dream is the same volume across all biomes, like all other songs.

Observed Result

Floating Dream is louder in Lush Caves than anywhere else.