Pass manifest to ClusteringDiarizer
**Is your feature request related to a problem? Please describe.**

Clustering diarizer class accepts paths to audiofiles instead of a manifest as all other models, however it still converts it to a NeMo-like manifest inside path2audio_files_to_manifest function. 

**Describe the solution you'd like**

An option to provide a manifest instead of a list of paths, e.g.
```python
assert paths2audio_files is not None or manifest_path is not None
if manifest_path is None:
   manifest = path2audio_files_to_manifest(paths2audio_files)    
```
