Unable to call install command multiple times

[tomgreenfield]

Error

Copied from adapt-security/adapt-authoring#280:

We're currently not able to run the CLI in parallel, as errors are thrown (think this could be caused by some kind of global scope).

An array of promises is being returned for each invocation of the install command when run in parallel, instead of a single resolved/rejected promise.

To reproduce

In framework directory:

1. Add installParallel.js:

   (async function() {
     const cli = require('adapt-cli').api.commands;
     const plugins = [
       'adapt-contrib-accordion',
       'adapt-contrib-slider',
       'adapt-contrib-vanilla'
     ];
     const results = await Promise.allSettled(plugins.map(plugin => cli.install(plugin)));
     results.forEach((result, i) => console.log(plugins[i], result.value || result.reason));
   }());

2. Run:

   npm install adapt-cli
   node installParallel