Add steps for document of getting dataset 'SF Bilingual Speech'

[RobinDong]

What does this PR do ?

When following the document to get dataset SFSpeech Chinese/English Bilingual Speech, the first command

python scripts/dataset_processing/tts/sfbilingual/get_data.py \
    --data-root <your_local_dataset_root> \
    --val-size 0.1 \
    --test-size 0.2 \
    --seed-for-ds-split 100

directly raise error:

Traceback (most recent call last):
  File "/home/xxx/NeMo/scripts/dataset_processing/tts/sfbilingual/get_data.py", line 122, in <module>
    main()
  File "/home/xxx/NeMo/scripts/dataset_processing/tts/sfbilingual/get_data.py", line 116, in main
    __process_data(
  File "/home/xxx/NeMo/scripts/dataset_processing/tts/sfbilingual/get_data.py", line 91, in __process_data
    entries = __process_transcript(dataset_path)
  File "/home/xxx/NeMo/scripts/dataset_processing/tts/sfbilingual/get_data.py", line 65, in __process_transcript
    with open(file_path / "text_SF.txt", encoding="utf-8") as fin:
FileNotFoundError: [Errno 2] No such file or directory: 'tryit/text_SF.txt'

The reason: scripts/dataset_processing/tts/sfbilingual/get_data.py actually doesn't download the dataset. The SFSpeech Chinese/English Bilingual Speech could only be downloaded through Nvidia NGC.

Changelog

• Add steps in the document of dataset SFSpeech to download by ngc-cli tool at first

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PR Type:

• New Feature
• Bugfix
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Who can review?

@blisc @okuchaiev @titu1994 @XuesongYang

[XuesongYang]

Thanks for the fix. I made some changes upon yours.