`NPMDependencyVersionChecker` `_jsonPath` is null if `basedir` = `/`

[trevordevore]

While working on a Docker file I encountered a problem where a version check performed by ember-cli-version-checker would fail when running in Docker. The error occurred because the Ember app source files were stored at the root of the drive.

In /src/npm-dependency-version-checker.js the following code is used for the _jsonPath property:

this._jsonPath = resolvePackage(this.name, basedir);

If basedir is / then this._jsonPath ends up being null. So this Docker file would lead to an error:

FROM node:14.16.0

# Copy the main application.
COPY . ./

...
ember build

This Docker file works correctly though:

FROM node:14.16.0

# Copy the main application.
COPY . ./my-ember-app
WORKDIR my-ember-app

...
ember build