Added type equivalence dict test (#231)
Added type equivalence dict test (#231)

* Added type equivalence dict test

* Nits

* Nit

* Nits

* Nit

* Changed list equality to set equality

* Fixed typo

* Asserted that there is one type equivalence in test_type_equivalence_dicts

kensho-technologies/graphql-compiler,kensho-technologies/graphql-compiler