Load ub_cfg from hydra config
# What does this PR do ?

Remove the need to load the yaml module inside GPT model and use hydra config instead.

**Collection**: nlp

# Changelog 
- For ub_tp_comm_overlap_cfg config field you no longer provide a path to the config but the whole config instead.

# Usage
If you add to your main config:
```yaml
defaults:
  [...]
  - optional tp_overlap@model.ub_tp_comm_overlap_cfg:
```
then you can load the config from a known location like this:
` ++  tp_overlap@model.ub_tp_comm_overlap_cfg=<tp_config}`

# 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

## Who can review?

Anyone in the community is free to review the PR once the checks have passed. 
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# Additional Information
* Related to # (issue)
