Fix ipywidgets error in asr notebook
Thanks for the PR, could you sign your commit according to the instructions on the dco bot ?(https://github.com/NVIDIA/NeMo/pull/2199/checks?check_run_id=2563046850)
 @titu1994 done with the signoff Thanks for the fix !
Added `ipywidgets` to avoid `ImportError: IProgress not found. Please update jupyter and ipywidgets. See https://ipywidgets.readthedocs.io/en/stable/user_install.html` error.