Added Hindi and Marathi Models in Nemo pretrained ASR_CTC_BPE models …
Signed-off-by: Megh Makwana [mmakwana@nvidia.com](mailto:mmakwana@nvidia.com)
# What does this PR do ?
Add new pretrained Hindi and Marathi ASR models (Conformer CTC Medium) to list_available_models and to documentation

Collection: [Note which collection this PR will affect]
ASR

# Changelog 
Add new pretrained Hindi and Marathi ASR models (Conformer CTC Medium) to the method list_available_models in EncDecCTCModelBPE 


# Usage

Import pretrained Hindi and Marathi Conformer-CTC-Medium Models
```python
asr_model = nemo_asr.models.EncDecCTCModelBPE.from_pretrained(model_name="stt_hi_conformer_ctc_medium")
asr_model = nemo_asr.models.EncDecCTCModelBPE.from_pretrained(model_name="stt_mr_conformer_ctc_medium")  
```

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**PR Type**:
- [ ] New Feature
- [ ] Bugfix
- [ ] Documentation

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# Additional Information
* Related to # (issue)
