version of dependency doesn't update in node_modules if you change it in package.json

Environment
Provide version numbers for the following components (information can be retrieved by running tns info in your project folder or by inspecting the package.json of the project):

• CLI: 6.0.2

Describe the bug
Change a version of a dependency in a package.json and run the project. You will see that the version doesn't update in node_modules.

To Reproduce

1. tns create app --js
2. set nativescript-dev-webpack to be 1.0.1 in package.json and run app
3. You will see that the version in node_modules/nativescript-dev-webpack/package.json is 1.0.2

Expected behavior
version should update

先使用 tns create app --js 重现问题，然后在运行应用后，将 package.json 中的依赖版本与 node_modules/nativescript-dev-webpack/package.json 进行比较。跟踪 CLI 的依赖安装或项目运行入口点；完成的标准是，更改请求的版本会更新已安装的依赖，而不是继续保留 1.0.2。