Drop unused torchaudio from devel requirements

torchaudio is not imported anywhere in the repo, but CI's adjust-torch-versions.py
pins it in lockstep with torch. torchaudio stopped tracking torch releases after
2.11 ('compatible with future versions of torch'), so on torch 2.14 CI resolves
torchaudio==2.14.0, which does not exist, and every job fails at dependency
install before running a single test.

Author: bhimrazy

requirements/devel.txt

@@ -6,4 +6,3 @@ datasets>=3.5.0
 peft>=0.15.2
 
 torchvision
-torchaudio