Remove 'require' test as bufferutil now ships prebuilt

test/unit/require.js

@@ -1,15 +0,0 @@
-'use strict';
-
-/* eslint no-unused-vars: ["error", { "varsIgnorePattern": "(bufferutil|sharp)" }] */
-
-describe('Require-time checks', function () {
-  /**
-    Including sharp alongside another C++ module that does not require
-    -stdlib=libc++ (for its C++11 features) has caused clang/llvm to
-    segfault due to the use of static function variables.
-  */
-  it('Require alongside C++ module that does not use libc++', function () {
-    const bufferutil = require('bufferutil');
-    const sharp = require('../../');
-  });
-});