Use pip version of Whisper

Closes #26 #25

auto_subtitle/cli.py

@@ -47,9 +47,6 @@ def main():
     if srt_only:
         return
 
-    # bash command to download a youtube video with `youtube-dl` and save it as `video.mp4`:
-    # youtube-dl -f 22 -o video.mp4 https://www.youtube.com/watch?v=QH2-TGUlwu4
-
     for path, srt_path in subtitles.items():
         out_path = os.path.join(output_dir, f"{filename(path)}.mp4")
 
@@ -58,7 +55,7 @@ def main():
         video = ffmpeg.input(path)
         audio = video.audio
 
-        stderr = ffmpeg.concat(
+        ffmpeg.concat(
             video.filter('subtitles', srt_path, force_style="OutlineColour=&H40000000,BorderStyle=3"), audio, v=1, a=1
         ).output(out_path).run(quiet=True, overwrite_output=True)