fix(API): isValidNativeScriptProject returns incorrect result

[rosen-vladimirov]

In case CLI is used as a library and isValidNativeScriptProject is called multiple times, it does not return correct results after the first time.
The problem is that it uses the singleton object - projectData. Change the implementation to use projectDataService, this way the method will always return correc results.

PR Checklist

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What is the current behavior?

In case CLI is used as a library and isValidNativeScriptProject is called multiple times, it does not return correct results after the first time.

What is the new behavior?

In case CLI is used as a library and isValidNativeScriptProject is called multiple times, it returns correct results.