calculateWitness() does not emit an error if there are missing inputs

[weijiekoh]

The following code runs without an error:

const wc = await WitnessCalculatorBuilder(wasm, options)
const witness = await wc.calculateWitness( { }, true)

The circuit in question, however, has three public input signals. calculateWitness should emit an error if any of the signals is not provided.

See https://github.com/weijiekoh/circom_runtime_bug for a demonstration of this error.