feat(yarn): implement get cache directory path and remove npm --dry-run logic

[Fatme]

Remove the last hardcoded npm command so yarn will be used all the time when it is set as package manager. Also remove --dry run logic and use $pacoteService.manifest instead.

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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• Tests for the changes are included.

rel to: #2737

[Fatme]

run ci