title: Upload an excel file using Cypress
body: <p>I using this <a href="https://www.npmjs.com/package/cypress-file-upload" rel="nofollow noreferrer">https://www.npmjs.com/package/cypress-file-upload</a> package for the file upload. 
  When I try to upload an excel (xlsx, xls) I get an error about the encoding.</p>
  
  <blockquote>
    <p>[cypress-file-upload error]: "encoding" is not valid.
    Please look into docs to find supported "encoding" values</p>
  </blockquote>
  
  <p>I have the following code:</p>
  
  <pre><code>const fileName = 'file_example_XLSX_1000.xlsx'
  cy.fixture('files used for testing/file_example_XLSX_1000.xlsx').then(fileContent =&gt; {
  cy.get('#file').upload({ fileContent, fileName, mimeType: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet', encoding: 'UTF - 8', }){ subjectType: 'input' }})
  </code></pre>