no such file or directory for wav file

Hello,

after I tried to solve the reCaptcha, then I got this message

`[Error: ENOENT: no such file or directory, open '/var/folders/5k/103mnjwx2rncp6btbvlt5z980000gn/T/reSOLVER-9454634224111578/out.wav'] {
errno: -2,
code: 'ENOENT',
syscall: 'open',
path: '/var/folders/5k/103mnjwx2rncp6btbvlt5z980000gn/T/reSOLVER-9454634224111578/out.wav',
name: 'ENOENTError'
}`

and I found there's a sound.mp3 file at that path, but not the Wav file.

thanks for this awesome library.

No source file or test is named. Start by tracing the reCAPTCHA audio flow and its temporary-file handling, comparing the reported sound.mp3 with the expected out.wav. Done means the flow no longer fails with ENOENT when opening the generated audio file.

Written by the indexing model from the issue text.