test: add test for pdf upload

cypress/integration/upload_spec.js

+describe('PDF submission test', () => {
+  it('can upload and submit a PDF', () => {
+    cy.visit('/dashboard')
+
+    const username = 'admin'
+    const password = 'password'
+
+    cy.get('input[name="username"]').type(username)
+    cy.get('input[name="password"]').type(password)
+    cy.get('button[type="submit"]').click()
+
+    cy.fixture('test-pdf.pdf', 'base64').then(fileContent => {
+      cy.get('[data-testid="dropzone"]').upload(
+        { fileContent, fileName: 'test-pdf.pdf', mimeType: 'application/pdf' },
+        { subjectType: 'drag-n-drop' },
+      )
+    })
+
+    cy.get('body').contains('Submission information')
+    cy.get('[data-testid="meta.title"]').contains('test pdf')
+  })
+})

cypress/support/commands.js

+import 'cypress-file-upload'
+
 // ***********************************************
 // This example commands.js shows you how to
 // create various custom commands and overwrite

package.json

@@ -86,6 +86,7 @@
     "copy-webpack-plugin": "^4.0.1",
     "css-loader": "^0.28.4",
     "cypress": "^3.7.0",
+    "cypress-file-upload": "^3.5.0",
     "eslint": "^4.12.0",
     "eslint-config-pubsweet": "^0.0.6",
     "eslint-plugin-import": "^2.8.0",