chore: use .js for bin files

Author: yyx990803

packages/@vue/cli-service/bin/vue-cli-service renamed to packages/@vue/cli-service/bin/vue-cli-service.js

@@ -4,7 +4,7 @@
   "description": "local service for vue-cli projects",
   "main": "lib/Service.js",
   "bin": {
-    "vue-cli-service": "bin/vue-cli-service"
+    "vue-cli-service": "bin/vue-cli-service.js"
   },
   "repository": {
     "type": "git",

packages/@vue/cli-service/package.json

@@ -3,7 +3,7 @@
   "version": "3.0.0-alpha.5",
   "description": "Command line interface for rapid Vue.js development",
   "bin": {
-    "vue": "bin/vue"
+    "vue": "bin/vue.js"
   },
   "files": [
     "bin",