CLIP Score Fusion model implementation
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# What does this PR do ?

Implemented ClipScoreFusion model (UniIR) which leverages Clip models for multimodal retrieval tasks

**Collection**: [Note which collection this PR will affect]
multimodal


# Usage

```python
model = MegatronCLIPScoreFusionModel(cfg.model, trainer)
```


# 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)
- [ ] Did you write any new necessary tests?
- [ ] 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**:
- [x] New Feature
- [ ] Bugfix
- [ ] Documentation

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


## Who can review?
@JRD971000 


