tfds version issue

[joocjun]

I was trying to load qrecc and wiki_dialog from the dialogue section to find that the current tfds version installed by requirements doesn't include them. Updating the version seemed to fix it. I haven't checked if this particular update causes any problems in other areas, but if it seems okay could you update the version of tfds in the requirements?

[shayne-longpre]

@joocjun Thank you for your suggestion! To clarify, were you using the flan/requirements.txt file, or flan/v2/requirements.txt? For v2 we only want to use the latter. Maybe I can add a note to the README