Add circleci config similar to one in gshard (#2677)
Add circleci config similar to one in gshard (#2677)

Summary:
# Before submitting

- [ ] Was this discussed/approved via a Github issue? (no need for typos, doc improvements)
- [ ] Did you read the [contributor guideline](https://github.com/pytorch/fairseq/blob/main/CONTRIBUTING.md)?
- [ ] Did you make sure to update the docs?
- [ ] Did you write any new necessary tests?

## What does this PR do?
Adds circleCI config to `main` similar to the one added in https://github.com/fairinternal/fairseq-py/issues/2455 by vedanuj
Splitting out changes in https://github.com/fairinternal/fairseq-py/issues/2570 to be cleaner.

## 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?
Make sure you had fun coding �

Pull Request resolved: https://github.com/fairinternal/fairseq-py/pull/2677

Reviewed By: Mortimerp9

Differential Revision: D32653411

Pulled By: dianaml0

fbshipit-source-id: 24950ecebfb569b552675e65bee1451b8070f8ee

pytorch/fairseq,pytorch/fairseq,pytorch/fairseq