text: Title: Background upscale isn't working  /  Real-ESRGAN ignored?
  Body: Hello, Thank you for this great project! 💙
  
  I'm running this on Windows 10 and Anaconda, Installation was very easy and simple to follow thanks to your step-by-step instructions, I appreciate it.
  
  ### Problem Description:
  I've added the argument: --bg_upsampler realesrgan
  But it seems to ignore it and just upscale the face  without the background, I get this warning:
  
  ```
  inference_codeformer.py:22: RuntimeWarning: The unoptimized RealESRGAN is slow on CPU. We do not use it. If you really want to use it, please modify the corresponding codes.
    warnings.warn('The unoptimized RealESRGAN is slow on CPU. We do not use it. '
  Face detection model: retinaface_resnet50
  Background upsampling: False, Face upsampling: False
  Processing: 5a.png
          detect 1 faces
  
  All results are saved in results/_SOURCE__0.7
  ```
  
  Since I'm not a programmer I don't know how to fix or mess with code in general,
  Can you please tell me how to make it work?
  
  Thanks ahead!