title: Use Graphql mutation in Cypress command
body: <p>I want to add a <code>cy.signUp</code> command to Cypress in the <code>commands.js</code> file.
  The frontend app uses Graphql with React to communicate with the backend app.</p>
  <p>I can't figure out a way to use a mutation inside of the <code>commands.js</code> file since the <a href="https://www.apollographql.com/docs/react/data/mutations/" rel="nofollow noreferrer">documentation</a> only offers to use it with React.</p>
  <p>How can I use graphql inside of this file to add a new command based on a mutation?</p>