Fix sdist builds by including headers (#1309)

Summary:
### Motivation
Fixes #1307

### Changes proposed

Includes headers in sdist

Pull Request resolved: #1309

Test Plan:
See `deploy.yml` changes

### Types of changes
- [ ] Docs change / refactoring / dependency upgrade
- [x] 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
- [x] My code follows the code style of this project.
- [ ] My change requires a change to the documentation.
- [ ] I have updated the documentation accordingly.
- [x] I have read the **[CONTRIBUTING](https://github.com/facebookresearch/beanmachine/blob/main/CONTRIBUTING.md)** document.
- [x] I have added tests to cover my changes.
- [ ] All new and existing tests passed.
- [ ] The title of my pull request is a short description of the requested changes.

Reviewed By: wtaha

Differential Revision: D33587287

Pulled By: feynmanliang

fbshipit-source-id: 825dc3c60b9ea9d76955cbd8e97645bacdae54a2

.github/workflows/deploy.yml

@@ -57,6 +57,10 @@ jobs:
       if: matrix.os == 'macos-latest'
       run: python -m build --sdist
 
+    - name: Install from sdist
+      if: matrix.os == 'macos-latest'
+      run: pip install dist/*.tar.gz
+
     - name: Install built Bean Machine dist
       run: pip install dist/*.whl
 

MANIFEST.in

@@ -0,0 +1 @@
+recursive-include src/beanmachine/graph *.h