fix: fix yarn view method to return correct data

[Fatme]

As --json flag is hardcoded for yarn info command, it always returns a json object in following format: { data: someResult }. As the other methods expect only someResult as a result from view command, we need to return .data property from yarn info output.

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What is the current behavior?

tns doctor does not return the correct components info when yarn is set as package manager.

What is the new behavior?

tns doctor returns the correct components info when yarn is set as package manager.

Fixes/Implements/Closes #[Issue Number].

Rel to: #2737