Summary:
Make all properties of `ModuleTraansportLike` covariant to enforce read-only behavior at all sites using it.
The type only exists for compatibility reasons between old and new output functionality, and covariant properties give us stronger guarantees.
Reviewed By: jeanlauliac
Differential Revision: D5111667
fbshipit-source-id: 674658b07eb3a229cbc4344cb636e4a9ea4126d1