fix(plugins): parse name issue with invalid plugins

[NathanWalker]

PR Checklist

• The PR title follows our guidelines: https://github.com/NativeScript/NativeScript/blob/master/tools/notes/CONTRIBUTING.md#commit-messages.
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What is the current behavior?

If a plugin contains invalid data like the wrong name according to package.json, a 'path' from 'undefined' ambiguous error occurs.

What is the new behavior?

This will now print the name of the invalid package to allow one to resolve effectively.

Fixes/Implements/Closes #[Issue Number].