Use sass-embedded as govuk-frontend now does

Author: BenSurgisonGDS

__tests__/spec/build.js

@@ -7,7 +7,7 @@ const path = require('path')
 const del = require('del')
 const fse = require('fs-extra')
 const fs = require('graceful-fs') // fs-extra uses graceful-fs, so we need to mock that instead of fs
-const sass = require('sass')
+const sass = require('sass-embedded')
 
 // local dependencies
 const { mkdtempSync } = require('../utils')

__tests__/spec/sanity-checks.js

@@ -7,7 +7,7 @@ const path = require('path')
 // npm dependencies
 const fse = require('fs-extra')
 const request = require('supertest')
-const sass = require('sass')
+const sass = require('sass-embedded')
 
 // local dependencies
 const { mkPrototype, mkdtempSync } = require('../utils')

lib/build.js

@@ -6,7 +6,7 @@ const path = require('path')
 const del = require('del')
 const fse = require('fs-extra')
 const fs = require('fs')
-const sass = require('sass')
+const sass = require('sass-embedded')
 
 // local dependencies
 const plugins = require('./plugins/plugins')