Summary:
- adds a test to check that `setFlexBasisAuto` is here
Pull Request resolved: https://github.com/facebook/yoga/pull/1225
Reviewed By: javache
Differential Revision: D43150473
Pulled By: NickGerleman
fbshipit-source-id: b5b82fe4a5db069d3ed5672990c9b8ade9141296