Tutorials and Docs for Multi-scale Diarization Decoder
# What does this PR do ?

This PR adds tutorials and documentations for the newly published model "Multi-scale diarization decoder".

Not only tutorial and docs, we need to ha

**Collection**: ASR 

# Changelog 

Major updated files:
`tutorials/speaker_tasks/Speaker_Diarization_Inference.ipynb`
`tutorials/speaker_tasks/Speaker_Diarization_Training.ipynb`
`docs/source/asr/speaker_diarization/*.rst` files

Minor updates: 
Some changes are made to use a model published on NGC.
`nemo/collections/asr/models/msdd_models.py`
`nemo/collections/asr/models/clustering_diarizer.py`


# Usage
* You can potentially add a usage example below

These are tutorials and documents.

# Before your PR is "Ready for review"
**Pre checks**:
- [x] Make sure you read and followed [Contributor guidelines](https://github.com/NVIDIA/NeMo/blob/main/CONTRIBUTING.md)
- [x] Did you write any new necessary tests?
- [x] Did you add or update any necessary documentation?
- [ ] Does the PR affect components that are optional to install? (Ex: Numba, Pynini, Apex etc)
  - [ ] Reviewer: Does the PR have correct import guards for all optional libraries?
  
**PR Type**:
- [ ] New Feature
- [ ] Bugfix
- [x] Documentation

If you haven't finished some of the above items you can still open "Draft" PR.


## Who can review?

NeMo ASR contributors

