Delete .circleci directory (#28)

Summary:
# PR Details

## Description

## Related Issue

## Motivation and Context

Pull Request resolved: #28

Test Plan:
## Types of changes

- [ ] Docs change
- [ ] Refactoring
- [ ] Dependency upgrade
- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing functionality to change)

## Checklist

- [ ] My code follows the code style of this project.
- [ ] I have run clang-format.
- [ ] My change requires a change to the documentation.
- [ ] I have updated the documentation accordingly.
- [ ] I have read the **CONTRIBUTING** document.
- [ ] I have added tests to cover my changes.
- [ ] All new and existing tests passed, including in ASAN and TSAN modes (if available on your platform).

Reviewed By: graphicsMan

Differential Revision: D54811901

Pulled By: bigfootjon

fbshipit-source-id: c21885d00187efdf361d4d08b7802cf073b4bfb2

Author: bigfootjon