Bump walk-sync from 1.1.4 to 2.0.2 (#298)

Bump walk-sync from 1.1.4 to 2.0.2

Author: Robert Jackson

package.json

@@ -45,7 +45,7 @@
     "mkdirp": "^0.5.1",
     "semver": "^6.3.0",
     "strip-bom": "^3.0.0",
-    "walk-sync": "^1.1.3"
+    "walk-sync": "^2.0.2"
   },
   "devDependencies": {
     "@ember/optional-features": "^1.0.0",