add normalise.css (needed for ember-styleguide tests)

Author: mansona

package.json

@@ -87,6 +87,7 @@
     "loader.js": "^4.7.0",
     "mocha": "^8.4.0",
     "module-name-inliner": "link:./tests/dummy/lib/module-name-inliner",
+    "normalize.css": "^8.0.1",
     "prettier": "^3.1.1",
     "qunit": "^2.20.0",
     "qunit-dom": "^2.0.0",