Update vue-property-decorator to v9 in vue 2 projects

[Mikilll94]

What problem does this feature solve?

Right now when scaffolding new Vue 2 project with TypeScript and class components, vue-cli installs:

    "vue-class-component": "^7.2.3",
    "vue-property-decorator": "^8.4.2"

The latest version of vue-property-decorator is v9.1.2 and this version should be installed.

What does the proposed API look like?

For Vue 2 project with TypeScript and class components, install the latest versions of vue-class-component and vue-property-decorator.

[haoqunjiang]

Fixed in 4.5.10