Please Fix dependency issues?

# Before submitting - [ ] Was this discussed/approved via a Github issue? (no need for typos, doc improvements) - [ x] Did you read the [contributor guideline](https://github.com/pytorch/fairseq/blob/main/CONTRIBUTING.md)? - [x ] Did you make sure to update the docs? - [x ] Did you write any new necessary tests? ## What does this PR do? Fixes multiple issues with older versions of omegaconf and hydra-core being hardcoded. ## PR review Anyone in the community is free to review the PR once the tests have passed. If we didn't discuss your PR in Github issues there's a high chance it will not be merged. ## Did you have fun? Of course.