test(api/api_test.cc): Add CheckSatisfiabilityMixedBooleanAndContinuous
test(api/api_test.cc): Add CheckSatisfiabilityMixedBooleanAndContinuous

soonho-tri/dreal4,soonho-tri/dreal4,dreal/dreal4,dreal/dreal4,soonho-tri/dreal4,dreal/dreal4,dreal/dreal4,soonho-tri/dreal4