Fix build doc (#3349)

Summary:
Follow-up https://github.com/pytorch/audio/issues/3045
- Revert the removal of HW acceleration doc
- comment out FFmpeg CLI test run

Pull Request resolved: https://github.com/pytorch/audio/pull/3349

Reviewed By: nateanl

Differential Revision: D46121899

Pulled By: mthrok

fbshipit-source-id: dfc030a69f05addec73637cfb6a720c184e37323

.github/workflows/build_docs.yml

@@ -91,8 +91,8 @@ jobs:
             make -j > /dev/null 2>&1
             make install
             # test
-            src="https://download.pytorch.org/torchaudio/tutorial-assets/stream-api/NASAs_Most_Scientifically_Complex_Space_Observatory_Requires_Precision-MP4_small.mp4"
-            ffmpeg -y -vsync 0 -hwaccel cuvid -hwaccel_output_format cuda -c:v h264_cuvid -resize 360x240 -i "${src}" -c:a copy -c:v h264_nvenc -b:v 5M test.mp4
+            # src="https://download.pytorch.org/torchaudio/tutorial-assets/stream-api/NASAs_Most_Scientifically_Complex_Space_Observatory_Requires_Precision-MP4_small.mp4"
+            # ffmpeg -y -vsync 0 -hwaccel cuvid -hwaccel_output_format cuda -c:v h264_cuvid -resize 360x240 -i "${src}" -c:a copy -c:v h264_nvenc -b:v 5M test.mp4
         )
 
         # Install PyTorch

docs/source/index.rst

@@ -44,6 +44,7 @@ model implementations and application components.
    tutorials/streamreader_advanced_tutorial
    tutorials/streamwriter_basic_tutorial
    tutorials/streamwriter_advanced
+   hw_acceleration_tutorial
 
    tutorials/effector_tutorial
    tutorials/audio_resampling_tutorial