fix IndexError

[wkpark]

Description

      File "F:\webui\webui\stable-diffusion-webui\modules\processing.py", line 734, in process_images
        res = process_images_inner(p)
      File "F:\webui\webui\stable-diffusion-webui\extensions\sd-webui-controlnet\scripts\batch_hijack.py", line 42, in processing_process_images_hijack
        return getattr(processing, '__controlnet_original_process_images_inner')(p, *args, **kwargs)
      File "F:\webui\webui\stable-diffusion-webui\modules\processing.py", line 989, in process_images_inner
        info=infotexts[0],
    IndexError: list index out of range
...

• fix IndexError: list index out of range error when interrupted while postprocessing
• This fix simply adds a default infotext

Checklist:

• I have read contributing wiki page
• I have performed a self-review of my own code
• My code follows the style guidelines
• My code passes tests