fix: Fix acorn-walk dependency (#138)

Fixes #137

Author: lucpotage

package.json

@@ -45,6 +45,7 @@
   "dependencies": {
     "@kazupon/vue-i18n-loader": "^0.3.0",
     "acorn": "^6.0.2",
+    "acorn-walk": "^6.1.0",
     "cookie": "^0.3.1",
     "js-cookie": "^2.2.0",
     "vue-i18n": "^8.1.0",