Wav2vec fix
# What does this PR do ?
- Quick fix to Jenkins CI config for Wav2Vec.
Add a one line overview of what this PR aims to accomplish.
- Halved number of conformer blocks and feedforward parameters to ease up memory requirements on Jenkins
**Collection**: [Note which collection this PR will affect]
- ASR
# Changelog 
- Halved transformer layers in wav2vec_ci (12 -> 6)
- Halved inner dimension of transformer encoder. (3072 -> 1536)
- Reduced batch size for wav2vec_ci to 8

# Before your PR is "Ready for review"
**Pre checks**:
- [Y ] Make sure you read and followed [Contributor guidelines](https://github.com/NVIDIA/NeMo/blob/main/CONTRIBUTING.md)
- [ N] Did you write any new necessary tests?
- [ N] Did you add or update any necessary documentation?
- [ N] 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
- [Y ] Bugfix
- [ ] Documentation


## Who can review?

Anyone in the community is free to review the PR once the checks have passed. 
[Contributor guidelines](https://github.com/NVIDIA/NeMo/blob/main/CONTRIBUTING.md) contains specific people who can review PRs to various areas.

# Additional Information
* Related to # (issue)
