Fix Jest diff call (#17921)

Author: gaearon

fixtures/dom/src/toWarnDev.js

@@ -1,7 +1,7 @@
 // copied from scripts/jest/matchers/toWarnDev.js
 'use strict';
 
-const jestDiff = require('jest-diff');
+const jestDiff = require('jest-diff').default;
 const util = require('util');
 
 function shouldIgnoreConsoleError(format, args) {

scripts/jest/matchers/toWarnDev.js

@@ -1,6 +1,6 @@
 'use strict';
 
-const jestDiff = require('jest-diff');
+const jestDiff = require('jest-diff').default;
 const util = require('util');
 const shouldIgnoreConsoleError = require('../shouldIgnoreConsoleError');