fix: add (empty) settings.gradle file to mark build as independent

[madmas]

Solves #4995

Adding an settings.gradle file marks the gradle build as a independent build and avoids conflicts with other gradle build

PR Checklist

• The PR title follows our guidelines: https://github.com/NativeScript/NativeScript/blob/master/CONTRIBUTING.md#commit-messages.
• There is an issue for the bug/feature this PR is for. To avoid wasting your time, it's best to open a suggestion issue first and wait for approval before working on it.
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• All existing tests are passing: https://github.com/NativeScript/nativescript-cli/blob/master/CONTRIBUTING.md#contribute-to-the-code-base
• Tests for the changes are included.

What is the current behavior?

Build fails if a gradle build is part of the wrapping project.

What is the new behavior?

Build succeeds as expected.

Fixes/Implements/Closes #4995 .

[rosen-vladimirov]

test cli-build

[rosen-vladimirov]

test cli-build cli-android