Update dependency ember-css-modules to v2

Author: renovate[bot]

ember/package.json

@@ -66,7 +66,7 @@
     "ember-concurrency": "1.3.0",
     "ember-cookies": "0.5.2",
     "ember-cp-validations": "3.5.6",
-    "ember-css-modules": "1.3.4",
+    "ember-css-modules": "2.1.1",
     "ember-css-modules-sass": "1.1.0",
     "ember-event-helpers": "0.1.1",
     "ember-fetch": "8.0.4",