Cannot run r1.6.1 fastpitch_finetune.ipynb from scratch using Colab
**Describe the bug**

Trying to run tts/tutorials/fastpitch_finetune.ipynb from Colab, the first cell give the following error:

`Collecting nemo_toolkit[tts]
  Cloning https://github.com/NeMo/NeMo.git (to revision r1.6.1) to /tmp/pip-install-dikw_cg4/nemo-toolkit_dde310e4647c4385a9c5f59aa12c3537
  Running command git clone -q https://github.com/NeMo/NeMo.git /tmp/pip-install-dikw_cg4/nemo-toolkit_dde310e4647c4385a9c5f59aa12c3537
  fatal: could not read Username for 'https://github.com/': No such device or address
WARNING: Discarding git+https://github.com/NeMo/NeMo.git@r1.6.1#egg=nemo_toolkit[tts]. Command errored out with exit status 128: git clone -q https://github.com/NeMo/NeMo.git /tmp/pip-install-dikw_cg4/nemo-toolkit_dde310e4647c4385a9c5f59aa12c3537 Check the logs for full command output.
ERROR: Could not find a version that satisfies the requirement nemo-toolkit (unavailable) (from versions: 0.11.0b6.linux-x86_64, 0.8, 0.8.1, 0.8.2, 0.9.0, 0.10.0b0, 0.10.0b1, 0.10.0b2, 0.10.0b3, 0.10.0b4, 0.10.0b5, 0.10.0b6, 0.10.0b7, 0.10.0b8, 0.10.0b9, 0.10.0b10, 0.10.0, 0.10.1, 0.11.0b1, 0.11.0b2, 0.11.0b3, 0.11.0b4, 0.11.0b5, 0.11.0b8, 0.11.0b10, 0.11.0b11, 0.11.0b12, 0.11.0b14, 0.11.0, 1.0.0a4, 1.0.0b0, 1.0.0b1, 1.0.0b2, 1.0.0b3, 1.0.0rc1, 1.0.0, 1.0.1, 1.0.2, 1.1.0, 1.2.0, 1.3.0, 1.4.0, 1.5.0, 1.5.1, 1.6.0, 1.6.1)
ERROR: No matching distribution found for nemo-toolkit (unavailable)`

In addition, I've been using fastpitch_finetune.ipynb with my own dataset since months ago (Branch Main), and now I cannot run it anymore **since 3 days ago**. It gives me an error when finetuning hifigan in line 32 (sorry for the long output):

`env: HYDRA_FULL_ERROR=1 [NeMo W 2022-02-04 14:08:27 optimizers:52] Apex was not found. Using the lamb or fused_adam optimizer will error out. ################################################################################ ### WARNING, path does not exist: KALDI_ROOT=/mnt/matylda5/iveselyk/Tools/kaldi-trunk ### (please add 'export KALDI_ROOT=<your_path>' in your $HOME/.profile) ### (or run as: KALDI_ROOT=<your_path> python <your_script>.py) ################################################################################ [NeMo W 2022-02-04 14:08:28 experimental:28] Module <function get_argmin_mat at 0x7f6324ecccb0> is experimental, not ready for production and is not fully supported. Use at your own risk. [NeMo W 2022-02-04 14:08:28 experimental:28] Module <function getMultiScaleCosAffinityMatrix at 0x7f6324eccd40> is experimental, not ready for production and is not fully supported. Use at your own risk. [NeMo W 2022-02-04 14:08:28 experimental:28] Module <function parse_scale_configs at 0x7f6324ecc950> is experimental, not ready for production and is not fully supported. Use at your own risk. [NeMo W 2022-02-04 14:08:28 experimental:28] Module <function get_embs_and_timestamps at 0x7f6324ecc290> is experimental, not ready for production and is not fully supported. Use at your own risk. [NeMo W 2022-02-04 14:08:28 nemo_logging:349] /usr/local/lib/python3.7/dist-packages/hydra/_internal/defaults_list.py:251: UserWarning: In 'hifigan.yaml': Defaults list is missing `_self_`. See https://hydra.cc/docs/upgrades/1.0_to_1.1/default_composition_order for more information warnings.warn(msg, UserWarning) Traceback (most recent call last): File "hifigan_finetune.py", line 32, in <module> main() # noqa pylint: disable=no-value-for-parameter File "/usr/local/lib/python3.7/dist-packages/nemo/core/config/hydra_runner.py", line 105, in wrapper config_name=config_name, File "/usr/local/lib/python3.7/dist-packages/hydra/_internal/utils.py", line 378, in _run_hydra lambda: hydra.run( File "/usr/local/lib/python3.7/dist-packages/hydra/_internal/utils.py", line 214, in run_and_report raise ex File "/usr/local/lib/python3.7/dist-packages/hydra/_internal/utils.py", line 211, in run_and_report return func() File "/usr/local/lib/python3.7/dist-packages/hydra/_internal/utils.py", line 381, in <lambda> overrides=args.overrides, File "/usr/local/lib/python3.7/dist-packages/hydra/_internal/hydra.py", line 92, in run run_mode=RunMode.RUN, File "/usr/local/lib/python3.7/dist-packages/hydra/_internal/hydra.py", line 563, in compose_config from_shell=from_shell, File "/usr/local/lib/python3.7/dist-packages/hydra/_internal/config_loader_impl.py", line 145, in load_configuration from_shell=from_shell, File "/usr/local/lib/python3.7/dist-packages/hydra/_internal/config_loader_impl.py", line 262, in _load_configuration_impl ConfigLoaderImpl._apply_overrides_to_config(config_overrides, cfg) File "/usr/local/lib/python3.7/dist-packages/hydra/_internal/config_loader_impl.py", line 342, in _apply_overrides_to_config f"Could not delete from config. '{override.key_or_group}' does not exist." hydra.errors.ConfigCompositionException: Could not delete from config. 'model.sched' does not exist.`


**Steps/Code to reproduce bug**

Simply trying to execute the latest tts/tutorials/fastpitch_finetune.ipynb.

**Environment details**

Google Colab and Colab PRO +


Any help on this will be appreciated.

Thanks!