test: refactor test-require-exceptions

Updated regex for error assertion.

PR-URL: https://github.com/nodejs/node/pull/9882
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

test/parallel/test-require-exceptions.js

@@ -1,16 +1,16 @@
 'use strict';
-var common = require('../common');
-var assert = require('assert');
+const common = require('../common');
+const assert = require('assert');
 
 // A module with an error in it should throw
 assert.throws(function() {
   require(common.fixturesDir + '/throws_error');
-});
+}, /^Error: blah$/);
 
 // Requiring the same module again should throw as well
 assert.throws(function() {
   require(common.fixturesDir + '/throws_error');
-});
+}, /^Error: blah$/);
 
 // Requiring a module that does not exist should throw an
 // error with its `code` set to MODULE_NOT_FOUND