Add Python 3.7 to test workflow (#406)
Add Python 3.7 to test workflow (#406)

* Add python3.7

* add another

* lint

* Update ci.yml

* Update ci.yml

* Update ci.yml

Co-authored-by: Nicholas Rubin <0cfada7668dd1fcdaa8e32fd03639a35f9127e52@google.com>
quantumlib/OpenFermion-Cirq,quantumlib/OpenFermion-Cirq