The root package LICENSE is not included in packages having a custom publish directory

[patricklafrance]

A new feature has been introduce to include the root package LICENSE to all the packages distributed with Lerna that doesn't already have a license. #1465

It works great for packages that doesn't specify a custom publish directory. However when a custom publish directory is specified, the published package doesn't include the LICENSE.

Expected Behavior

The root package LICENSE file should also be included in packages having a custom publish directory.

// package.json

"publishConfig": {
    "directory": "dist"
}

Current Behavior

The root package LICENSE file is only included in packages that doesn't specify a custom publish directory.

Possible Solution

Steps to Reproduce (for bugs)

1. Create a new project with Lerna initialized
2. Add a package to the project (make sure it's handled by Lerna)
3. Configure a custom publish directory for the package (https://github.com/lerna/lerna/tree/master/commands/publish#per-package-configuration)
4. Publish the package with Lerna
5. Validate that the resulting package doesn't contains a LICENSE file

lerna.json

<!-- Please paste your `lerna.json` here -->

{
  "npmClient": "yarn",
  "useWorkspaces": true,
  "version": "independent"
}

lerna-debug.log

<!-- If you have a `lerna-debug.log` available, please paste it here -->
<!-- Otherwise, feel free to delete this <details> block -->

Context

Your Environment

Executable	Version
lerna --version	3.15.0
npm --version	6.9.0
yarn --version	1.16.0
node --version	10.11

OS	Version
NAME	VERSION
Windows 10	1803

[patricklafrance]

Thank you @evocateur really appreciated!