perf: use prompts instead of inquirer

[janoshrubos]

PR Checklist

• The PR title follows our guidelines: https://github.com/NativeScript/NativeScript/blob/master/CONTRIBUTING.md#commit-messages.
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• Tests for the changes are included.

What is the current behavior?

Using inquirer package

What is the new behavior?

Using prompts package instead of inquirer in the prompter.

[janoshrubos]

Yes, @rigor789 had the idea to replace the packages to reduce the size of the cli.

[rigor789]

Yep the goal was to reduce the CLI size!

Before (7.0.11):
239 369 798 bytes (286,7 MB on disk) for 17 350 items

After (this PR):
233 977 884 bytes (268,9 MB on disk) for 13 576 items

Diff:
-17,8 MB on disk
-3774 files

I think that's a decent reduction from a relatively small change!

/cc @NathanaelA @NathanWalker

[NathanaelA]

Looking at the code, I see nothing wrong and reducing the CLI dependencies is a good thing. Thanks!

LGTM...