Improve flow types for execute logic
Improve flow types for execute logic

graphql/graphql-js,enaqx/graphql-js,enaqx/graphql-js,tgriesser/graphql-js,graphql/graphql-js,jjergus/graphql-js,graphql/graphql-js,tgriesser/graphql-js,jjergus/graphql-js,enaqx/graphql-js