fix(demo): fixes vocoder step bug in demo (#458)
* Sets vocoder_global_step equal to 1 for demo
* Adds comments to dummy values
* style: apply black formatting
also remove unused import
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fixes https://github.com/roedoejet/EveryVoice/issues/453
Co-authored-by: Vladislav Govor <vlg000@5ae4028ef268>
Co-authored-by: Aidan Pine <hello@aidanpine.ca>
