[Refactor] Fix incorrect string formatting in addNPMDependencies

[gonzaloriestra]

What was improved

Fixed a minor code quality and formatting issue in addNPMDependencies where an array of dependency strings was being wrapped in another array before calling .join(' '). This resulted in a comma-separated string instead of a space-separated one.

How to test your changes?

Run any command that triggers addNPMDependencies and verify the "Installing ..." output message correctly space-separates multiple dependencies.

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PR created automatically by Jules for task 6314282184458645698 started by @gonzaloriestra

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