If you live in NJ, your income from PA is not taxable by PA, it is taxed by NJ since PA and NJ have a reciprocal tax agreement. This means, that your income is only taxed by the state you live in, not the state you work in.
You would only need to file a PA Non-Resident return if you are claiming a refund of taxes withheld. If you did have taxes withheld, when you file the PA non-resident return, you will enter $0 as your income and keep the amount of withholdings as they are reported.